{"id":2080,"date":"2025-02-14T10:26:47","date_gmt":"2025-02-14T03:26:47","guid":{"rendered":"https:\/\/www.pgtutorial.com\/?page_id=2080"},"modified":"2025-02-16T16:32:54","modified_gmt":"2025-02-16T09:32:54","slug":"postgresql-cast","status":"publish","type":"page","link":"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-cast\/","title":{"rendered":"PostgreSQL Cast"},"content":{"rendered":"\n<p><strong>Summary<\/strong>: In this tutorial, you&#8217;ll learn how to convert a value of one data type to another using the PostgreSQL <code>CAST()<\/code> function and operator.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='postgresql-cast-overview'>PostgreSQL Cast Overview <a href=\"#postgresql-cast-overview\" class=\"anchor\" id=\"postgresql-cast-overview\" title=\"Anchor for PostgreSQL Cast Overview\">#<\/a><\/h2>\n\n\n\n<p>To convert a value of one data type to another, you use the <code>CAST()<\/code> function or cast operator (<code>::<\/code>).<\/p>\n\n\n\n<p>Here&#8217;s the syntax of the <code>CAST()<\/code> function:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">CAST(<span class=\"hljs-keyword\">value<\/span> <span class=\"hljs-keyword\">AS<\/span> target_type);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this syntax:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>First, specify the <code>value<\/code> to cast.<\/li>\n\n\n\n<li>Second, provide the target data type (<code>target_type<\/code>) to which you want to convert the <code>value<\/code>.<\/li>\n<\/ul>\n\n\n\n<p>The <code>CAST()<\/code> function returns the value to cast to the target type. <\/p>\n\n\n\n<p>If the cast fails, the <code>CAST()<\/code> function issues an error.<\/p>\n\n\n\n<p>To make it more convenient, PostgreSQL offers the cast operator (<code>::<\/code>), which is more concise than the <code>CAST<\/code> function:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-2\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">value<\/span>::target_type<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-2\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>The cast operator (<code>::<\/code>) casts the value to the target type or raises an error if it fails.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-an-integer'>Casting a String to an Integer <a href=\"#casting-a-string-to-an-integer\" class=\"anchor\" id=\"casting-a-string-to-an-integer\" title=\"Anchor for Casting a String to an Integer\">#<\/a><\/h2>\n\n\n\n<p>The following statement uses the <code>CAST()<\/code> function to convert a string to an integer:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-3\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'10'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INT<\/span>) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-3\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJzEwJyBBUyBJTlQpIHJlc3VsdDs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-4\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> result\n<span class=\"hljs-comment\">--------<\/span>\n     <span class=\"hljs-number\">10<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-4\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Similarly, you can convert the string &#8217;10&#8217; to an integer using the cast operator:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-5\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-string\">'10'<\/span>::<span class=\"hljs-type\">INT<\/span> result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-5\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICcxMCc6OklOVCByZXN1bHQ7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>The following query issues an error because the <code>CAST()<\/code> function cannot convert the string &#8217;10x&#8217; to an integer:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-6\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'10x'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INT<\/span>) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-6\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJzEweCcgQVMgSU5UKSByZXN1bHQ7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-7\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">ERROR:  invalid <span class=\"hljs-keyword\">input<\/span> syntax <span class=\"hljs-keyword\">for<\/span> <span class=\"hljs-keyword\">type<\/span> <span class=\"hljs-type\">integer<\/span>: \"10x\"<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-7\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-a-double'>Casting a String to a Double <a href=\"#casting-a-string-to-a-double\" class=\"anchor\" id=\"casting-a-string-to-a-double\" title=\"Anchor for Casting a String to a Double\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST()<\/code> function to cast a string to a double:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-8\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'9.99'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">DOUBLE<\/span> <span class=\"hljs-type\">PRECISION<\/span>) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-8\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJzkuOTknIEFTIERPVUJMRSBQUkVDSVNJT04pIHJlc3VsdDs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-9\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> result\n<span class=\"hljs-comment\">--------<\/span>\n   <span class=\"hljs-number\">9.99<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-9\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Here&#8217;s how you use the cast operator(<code>::<\/code>):<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-10\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-string\">'9.99'<\/span>::<span class=\"hljs-type\">DOUBLE<\/span> <span class=\"hljs-type\">PRECISION<\/span> result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-10\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICc5Ljk5Jzo6RE9VQkxFIFBSRUNJU0lPTiByZXN1bHQ7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-a-boolean'>Casting a String to a Boolean <a href=\"#casting-a-string-to-a-boolean\" class=\"anchor\" id=\"casting-a-string-to-a-boolean\" title=\"Anchor for Casting a String to a Boolean\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST()<\/code> function to cast strings to boolean values:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-11\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'true'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">BOOLEAN<\/span>),\n  CAST(<span class=\"hljs-string\">'false'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">BOOLEAN<\/span>),\n  CAST(<span class=\"hljs-string\">'T'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">BOOLEAN<\/span>),\n  CAST(<span class=\"hljs-string\">'F'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">BOOLEAN<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-11\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJ3RydWUnIEFTIEJPT0xFQU4pLCBDQVNUKCdmYWxzZScgQVMgQk9PTEVBTiksIENBU1QoJ1QnIEFTIEJPT0xFQU4pLCBDQVNUKCdGJyBBUyBCT09MRUFOKTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-12\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> <span class=\"hljs-type\">bool<\/span> | <span class=\"hljs-type\">bool<\/span> | <span class=\"hljs-type\">bool<\/span> | <span class=\"hljs-type\">bool<\/span>\n<span class=\"hljs-comment\">------+------+------+------<\/span>\n t    | f    | t    | f<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-12\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Cast operator:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-13\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-string\">'true'<\/span>::<span class=\"hljs-type\">bool<\/span>,\n  <span class=\"hljs-string\">'false'<\/span>::<span class=\"hljs-type\">bool<\/span>,\n  <span class=\"hljs-string\">'T'<\/span>::<span class=\"hljs-type\">bool<\/span>,\n  <span class=\"hljs-string\">'F'<\/span>::<span class=\"hljs-type\">bool<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-13\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICd0cnVlJzo6Ym9vbCwgJ2ZhbHNlJzo6Ym9vbCwgJ1QnOjpib29sLCAnRic6OmJvb2w7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-a-date'>Casting a String to a Date <a href=\"#casting-a-string-to-a-date\" class=\"anchor\" id=\"casting-a-string-to-a-date\" title=\"Anchor for Casting a String to a Date\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST()<\/code> to convert a string to a date:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-14\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'2025-02-14'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">DATE<\/span>),\n  CAST(<span class=\"hljs-string\">'14-Feb-2025'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">DATE<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-14\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJzIwMjUtMDItMTQnIEFTIERBVEUpLCBDQVNUKCcxNC1GZWItMjAyNScgQVMgREFURSk7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-15\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">    <span class=\"hljs-type\">date<\/span>    |    <span class=\"hljs-type\">date<\/span>\n<span class=\"hljs-comment\">------------+------------<\/span>\n <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span> | <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-15\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-16\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-string\">'2025-02-14'<\/span>::<span class=\"hljs-type\">DATE<\/span>,\n  <span class=\"hljs-string\">'14-Feb-2025'<\/span>::<span class=\"hljs-type\">DATE<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-16\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICcyMDI1LTAyLTE0Jzo6REFURSwgJzE0LUZlYi0yMDI1Jzo6REFURTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-17\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">    <span class=\"hljs-type\">date<\/span>    |    <span class=\"hljs-type\">date<\/span>\n<span class=\"hljs-comment\">------------+------------<\/span>\n <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span> | <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-17\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In these examples, the <code>CAST()<\/code> function and operator convert the string <code>'2025-02-14'<\/code> and <code>'14-Feb-2025'<\/code> to dates.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-an-interval'>Casting a String to an Interval <a href=\"#casting-a-string-to-an-interval\" class=\"anchor\" id=\"casting-a-string-to-an-interval\" title=\"Anchor for Casting a String to an Interval\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST<\/code> function or operator to cast a string to an interval:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-18\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'2 hours 30 minutes'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INTERVAL<\/span>) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-18\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJzIgaG91cnMgMzAgbWludXRlcycgQVMgSU5URVJWQUwpIHJlc3VsdDs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-19\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">  result\n<span class=\"hljs-comment\">----------<\/span>\n <span class=\"hljs-number\">02<\/span>:<span class=\"hljs-number\">30<\/span>:<span class=\"hljs-number\">00<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-19\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-20\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span> <span class=\"hljs-string\">'2 hours 30 minutes'<\/span>::<span class=\"hljs-type\">INTERVAL<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-20\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICcyIGhvdXJzIDMwIG1pbnV0ZXMnOjpJTlRFUlZBTDs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output<strong>:<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-21\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> <span class=\"hljs-type\">interval<\/span>\n<span class=\"hljs-comment\">----------<\/span>\n <span class=\"hljs-number\">02<\/span>:<span class=\"hljs-number\">30<\/span>:<span class=\"hljs-number\">00<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-21\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-timestamp-to-a-date'>Casting a Timestamp to a Date <a href=\"#casting-a-timestamp-to-a-date\" class=\"anchor\" id=\"casting-a-timestamp-to-a-date\" title=\"Anchor for Casting a Timestamp to a Date\">#<\/a><\/h2>\n\n\n\n<p>The following statement uses the <code>CAST()<\/code> function to cast a timestamp to a date:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-22\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-type\">TIMESTAMP<\/span> <span class=\"hljs-string\">'2025-02-14 12:30:45'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">DATE<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-22\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoVElNRVNUQU1QICcyMDI1LTAyLTE0IDEyOjMwOjQ1JyBBUyBEQVRFKTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-23\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">    <span class=\"hljs-type\">date<\/span>\n<span class=\"hljs-comment\">------------<\/span>\n <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-23\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-24\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span> <span class=\"hljs-type\">TIMESTAMP<\/span> <span class=\"hljs-string\">'2025-02-14 12:30:45'<\/span>::<span class=\"hljs-type\">DATE<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-24\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIFRJTUVTVEFNUCAnMjAyNS0wMi0xNCAxMjozMDo0NSc6OkRBVEU7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output<strong>:<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-25\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">    <span class=\"hljs-type\">date<\/span>\n<span class=\"hljs-comment\">------------<\/span>\n <span class=\"hljs-number\">2025<\/span><span class=\"hljs-number\">-02<\/span><span class=\"hljs-number\">-14<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-25\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-an-interval-to-text'>Casting an Interval to Text <a href=\"#casting-an-interval-to-text\" class=\"anchor\" id=\"casting-an-interval-to-text\" title=\"Anchor for Casting an Interval to Text\">#<\/a><\/h2>\n\n\n\n<p>The following statement uses the <code>CAST()<\/code> function to cast an interval to a date:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-26\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-type\">INTERVAL<\/span> <span class=\"hljs-string\">'7 days'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">TEXT<\/span>) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-26\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoSU5URVJWQUwgJzcgZGF5cycgQVMgVEVYVCkgcmVzdWx0Ow%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-27\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> result\n<span class=\"hljs-comment\">--------<\/span>\n <span class=\"hljs-number\">7<\/span> days<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-27\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-double-precision-to-an-integer'>Casting a Double Precision to an Integer <a href=\"#casting-a-double-precision-to-an-integer\" class=\"anchor\" id=\"casting-a-double-precision-to-an-integer\" title=\"Anchor for Casting a Double Precision to an Integer\">#<\/a><\/h2>\n\n\n\n<p>The following statement uses the <code>CAST()<\/code> function to cast a double precision to an integer:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-28\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-number\">9.99<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INT<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-28\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoOS45OSBBUyBJTlQpOw%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output<strong>:<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-29\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> <span class=\"hljs-type\">int4<\/span>\n<span class=\"hljs-comment\">------<\/span>\n   <span class=\"hljs-number\">10<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-29\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-an-array-to-a-string'>Casting an Array to a String <a href=\"#casting-an-array-to-a-string\" class=\"anchor\" id=\"casting-an-array-to-a-string\" title=\"Anchor for Casting an Array to a String\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST()<\/code> function to cast an array to text:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-30\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  CAST(<span class=\"hljs-string\">'{10, 20, 30}'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">TEXT<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-30\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJ3sxMCwgMjAsIDMwfScgQVMgVEVYVCk7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-31\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">     <span class=\"hljs-type\">text<\/span>\n<span class=\"hljs-comment\">--------------<\/span>\n {<span class=\"hljs-number\">10<\/span>, <span class=\"hljs-number\">20<\/span>, <span class=\"hljs-number\">30<\/span>}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-31\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='casting-a-string-to-an-array'>Casting a String to an Array <a href=\"#casting-a-string-to-an-array\" class=\"anchor\" id=\"casting-a-string-to-an-array\" title=\"Anchor for Casting a String to an Array\">#<\/a><\/h2>\n\n\n\n<p>The following example uses the <code>CAST()<\/code> function to cast an array to text:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-32\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span> CAST(<span class=\"hljs-string\">'{10,20,30}'<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INT<\/span>&#91;]) result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-32\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIENBU1QoJ3sxMCwyMCwzMH0nIEFTIElOVFtdKSByZXN1bHQ7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-33\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">   result\n<span class=\"hljs-comment\">------------<\/span>\n {<span class=\"hljs-number\">10<\/span>,<span class=\"hljs-number\">20<\/span>,<span class=\"hljs-number\">30<\/span>}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-33\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-34\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-string\">'{10,20,30}'<\/span>::<span class=\"hljs-type\">INT<\/span>&#91;] result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-34\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICd7MTAsMjAsMzB9Jzo6SU5UW10gcmVzdWx0Ow%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-35\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">   result\n<span class=\"hljs-comment\">------------<\/span>\n {<span class=\"hljs-number\">10<\/span>,<span class=\"hljs-number\">20<\/span>,<span class=\"hljs-number\">30<\/span>}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-35\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='using-postgresql-cast-function-with-table-data'>Using PostgreSQL CAST Function with Table Data <a href=\"#using-postgresql-cast-function-with-table-data\" class=\"anchor\" id=\"using-postgresql-cast-function-with-table-data\" title=\"Anchor for Using PostgreSQL CAST Function with Table Data\">#<\/a><\/h2>\n\n\n\n<p>We&#8217;ll use the <code>products<\/code> table from the <code>inventory<\/code> table:<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"159\" height=\"254\" src=\"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png\" alt=\"PostgreSQL Cast: The products Table\" class=\"wp-image-1051\"\/><\/figure>\n\n\n\n<p>The following example uses the <code>CAST<\/code> function to cast a string to a number:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-36\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  product_name,\n  CAST((REGEXP_MATCH(product_name, <span class=\"hljs-string\">'\\d+'<\/span>)) &#91;<span class=\"hljs-number\">1<\/span>] <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-type\">INT<\/span>) number\n<span class=\"hljs-keyword\">FROM<\/span>\n  products;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-36\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIHByb2R1Y3RfbmFtZSwgQ0FTVCgoUkVHRVhQX01BVENIKHByb2R1Y3RfbmFtZSwgJ1xkKycpKSBbMV0gQVMgSU5UKSBudW1iZXIgRlJPTSBwcm9kdWN0czs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-37\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">        product_name        | number\n<span class=\"hljs-comment\">----------------------------+--------<\/span>\n Samsung Galaxy S24         |     <span class=\"hljs-number\">24<\/span>\n Apple iPhone <span class=\"hljs-number\">15<\/span>            |     <span class=\"hljs-number\">15<\/span>\n Huawei Mate <span class=\"hljs-number\">60<\/span>             |     <span class=\"hljs-number\">60<\/span>\n Xiaomi Mi <span class=\"hljs-number\">14<\/span>               |     <span class=\"hljs-number\">14<\/span>\n Sony Xperia <span class=\"hljs-number\">1<\/span> VI           |      <span class=\"hljs-number\">1<\/span>\n Samsung Galaxy Z Fold <span class=\"hljs-number\">5<\/span>    |      <span class=\"hljs-number\">5<\/span>\n...<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-37\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>How it works<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>First, extract the first occurrence of a number from the product name using the <code><a href=\"https:\/\/www.pgtutorial.com\/postgresql-string-functions\/postgresql-regexp_match\/\">REGEXP_MATCH<\/a><\/code> function.<\/li>\n\n\n\n<li>Second, use the <code>CAST<\/code> function to cast a string to an integer.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id='multiple-casting'>Multiple Casting <a href=\"#multiple-casting\" class=\"anchor\" id=\"multiple-casting\" title=\"Anchor for Multiple Casting\">#<\/a><\/h2>\n\n\n\n<p>The following query extracts the product price from an XML fragment and converts it to the decimal:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-38\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  (\n    xpath(\n      <span class=\"hljs-string\">'\/product\/price\/text()'<\/span>,\n      XMLPARSE(\n        <span class=\"hljs-keyword\">CONTENT<\/span> <span class=\"hljs-string\">'&lt;product&gt; &lt;name&gt;Smartphone&lt;\/name&gt; &lt;price&gt;999.99&lt;\/price&gt; &lt;\/product&gt;'<\/span>\n      )\n    )\n  ) &#91;<span class=\"hljs-number\">1<\/span>]::<span class=\"hljs-type\">TEXT<\/span>::<span class=\"hljs-type\">DEC<\/span> price;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-38\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUICggeHBhdGgoICcvcHJvZHVjdC9wcmljZS90ZXh0KCknLCBYTUxQQVJTRSggQ09OVEVOVCAnPHByb2R1Y3Q%2BIDxuYW1lPlNtYXJ0cGhvbmU8L25hbWU%2BIDxwcmljZT45OTkuOTk8L3ByaWNlPiA8L3Byb2R1Y3Q%2BJyApICkgKSBbMV06OlRFWFQ6OkRFQyBwcmljZTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-39\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> price\n<span class=\"hljs-comment\">--------<\/span>\n <span class=\"hljs-number\">999.99<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-39\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>How it Works<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The <code>xpath<\/code> function extracts a text from the price element of the <code>XML<\/code> fragment. It returns an array <code>{999.99}<\/code>.<\/li>\n\n\n\n<li><code>[1]<\/code> returns the first element of the result array <code>999.99<\/code>. The data is an <code>XML<\/code> value.<\/li>\n\n\n\n<li><code>::TEXT<\/code> casts the <code>XML<\/code> value to a value of <code>TEXT<\/code>.<\/li>\n\n\n\n<li><code>::DEC<\/code> casts the value of <code>TEXT<\/code> to <code>XML<\/code> value.<\/li>\n<\/ul>\n\n\n\n<p>Notice that you cannot cast type <code>XML<\/code> to numeric directly. The following statement will issue an error:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-40\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  (\n    xpath(\n      <span class=\"hljs-string\">'\/product\/price\/text()'<\/span>,\n      XMLPARSE(\n        <span class=\"hljs-keyword\">CONTENT<\/span> <span class=\"hljs-string\">'&lt;product&gt; &lt;name&gt;Smartphone&lt;\/name&gt; &lt;price&gt;999.99&lt;\/price&gt; &lt;\/product&gt;'<\/span>\n      )\n    )\n  ) &#91;<span class=\"hljs-number\">1<\/span>]::<span class=\"hljs-type\">DEC<\/span> price;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-40\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Error:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-41\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">ERROR:  cannot <span class=\"hljs-keyword\">cast<\/span> <span class=\"hljs-keyword\">type<\/span> <span class=\"hljs-type\">xml<\/span> <span class=\"hljs-keyword\">to<\/span> <span class=\"hljs-type\">numeric<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-41\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='implicit-casting'>Implicit Casting <a href=\"#implicit-casting\" class=\"anchor\" id=\"implicit-casting\" title=\"Anchor for Implicit Casting\">#<\/a><\/h2>\n\n\n\n<p>PostgreSQL can sometimes automatically cast a value to a specific one without requiring the <code>CAST<\/code> function or operator. For example:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-42\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  <span class=\"hljs-number\">1<\/span> + <span class=\"hljs-string\">'2'<\/span> result;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-42\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIDEgKyAnMicgcmVzdWx0Ow%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output<strong>:<\/strong><\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-43\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"> result\n<span class=\"hljs-comment\">--------<\/span>\n      <span class=\"hljs-number\">3<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-43\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this example, PostgreSQL automatically converts the string <code>'2'<\/code> to an integer and adds it to the number 1.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='custom-casts'>Custom casts <a href=\"#custom-casts\" class=\"anchor\" id=\"custom-casts\" title=\"Anchor for Custom casts\">#<\/a><\/h2>\n\n\n\n<p>You can create your cast for custom types using the <code>CREATE CAST<\/code> statement. <\/p>\n\n\n\n<p>Here&#8217;s the basic syntax of the <code>CREATE CAST<\/code> statement:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-44\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">CREATE<\/span> CAST (source_type <span class=\"hljs-keyword\">AS<\/span> target_type)\n<span class=\"hljs-keyword\">WITH<\/span>\n  <span class=\"hljs-keyword\">FUNCTION<\/span> function_name (arguments) <span class=\"hljs-keyword\">AS IMPLICIT<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-44\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Let&#8217;s see the following example.<\/p>\n\n\n\n<p>First, <a href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-composite-types\/\">create a composite type<\/a> that holds product data:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-45\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">CREATE<\/span> <span class=\"hljs-keyword\">TYPE<\/span> product_info <span class=\"hljs-keyword\">AS<\/span> (<span class=\"hljs-type\">name<\/span> <span class=\"hljs-type\">TEXT<\/span>, price <span class=\"hljs-type\">DEC<\/span>);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-45\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=Q1JFQVRFIFRZUEUgcHJvZHVjdF9pbmZvIEFTIChuYW1lIFRFWFQsIHByaWNlIERFQyk7\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Second, <a href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-create-function\/\">create a function<\/a> that converts a value of <a href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-json\/\">JSONB<\/a> to <code>product_info<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-46\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">CREATE<\/span> <span class=\"hljs-keyword\">FUNCTION<\/span> jsonb_to_product_info(data <span class=\"hljs-type\">JSONB<\/span>) \n<span class=\"hljs-keyword\">RETURNS<\/span> product_info \n<span class=\"hljs-keyword\">AS<\/span> \n$$<span class=\"pgsql\">\n<span class=\"hljs-keyword\">SELECT<\/span> \n    (data-&gt;&gt;<span class=\"hljs-string\">'name'<\/span>)::<span class=\"hljs-type\">TEXT<\/span>, \n    (data-&gt;&gt;<span class=\"hljs-string\">'price'<\/span>)::<span class=\"hljs-type\">DEC<\/span>;\n$$<\/span> \n<span class=\"hljs-keyword\">LANGUAGE<\/span> <span class=\"hljs-keyword\">SQL<\/span> <span class=\"hljs-keyword\">IMMUTABLE<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-46\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=Q1JFQVRFIEZVTkNUSU9OIGpzb25iX3RvX3Byb2R1Y3RfaW5mbyAoZGF0YSBKU09OQikgUkVUVVJOUyBwcm9kdWN0X2luZm8gQVMgJCQKU0VMRUNUIAogICAgKGRhdGEtPj4nbmFtZScpOjpURVhULCAKICAgIChkYXRhLT4%2BJ3ByaWNlJyk6OkRFQzsKJCQgTEFOR1VBR0UgU1FMIElNTVVUQUJMRTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Third, create a custom cast to convert a <code>JSONB<\/code> to <code>product_info<\/code> using the <code>jsonb_to_product_info<\/code> function:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-47\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">CREATE<\/span> CAST (<span class=\"hljs-type\">JSONB<\/span> <span class=\"hljs-keyword\">AS<\/span> product_info)\n<span class=\"hljs-keyword\">WITH<\/span>\n  <span class=\"hljs-keyword\">FUNCTION<\/span> jsonb_to_product_info (<span class=\"hljs-type\">JSONB<\/span>) <span class=\"hljs-keyword\">AS IMPLICIT<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-47\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=Q1JFQVRFIENBU1QgKEpTT05CIEFTIHByb2R1Y3RfaW5mbykKV0lUSAogIEZVTkNUSU9OIGpzb25iX3RvX3Byb2R1Y3RfaW5mbyAoSlNPTkIpIEFTIElNUExJQ0lUOw%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>In this statement:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>WITH FUNCTION jsonb_to_product_info(JSONB)<\/code>: Specifies the function <code>jsonb_to_product_info<\/code> to use for the cast.<\/li>\n\n\n\n<li><code>AS IMPLICIT<\/code>: Allows PostgreSQL to cast <code>JSONB<\/code> values when needed automatically.<\/li>\n<\/ul>\n\n\n\n<p>Fourth, <a href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-create-table\/\">create a table<\/a> called <code>product_prices<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-48\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">CREATE<\/span> <span class=\"hljs-keyword\">TABLE<\/span> product_prices (\n  id <span class=\"hljs-type\">INT<\/span> <span class=\"hljs-keyword\">GENERATED<\/span> <span class=\"hljs-keyword\">ALWAYS<\/span> <span class=\"hljs-keyword\">AS<\/span> <span class=\"hljs-keyword\">IDENTITY<\/span> <span class=\"hljs-keyword\">PRIMARY KEY<\/span>,\n  data <span class=\"hljs-type\">JSONB<\/span>\n);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-48\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=Q1JFQVRFIFRBQkxFIHByb2R1Y3RfcHJpY2VzICggaWQgSU5UIEdFTkVSQVRFRCBBTFdBWVMgQVMgSURFTlRJVFkgUFJJTUFSWSBLRVksIGRhdGEgSlNPTkIgKTs%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Fifth, insert some rows into the <code>product_prices<\/code> table:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-49\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">INSERT<\/span> <span class=\"hljs-keyword\">INTO<\/span>\n  product_prices (data)\n<span class=\"hljs-keyword\">VALUES<\/span>\n  (<span class=\"hljs-string\">'{\"name\": \"Smartphone\", \"price\": 999.99}'<\/span>),\n  (<span class=\"hljs-string\">'{\"name\": \"Smartwatch\", \"price\": 699.49}'<\/span>)\n<span class=\"hljs-keyword\">RETURNING<\/span>\n  data;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-49\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=SU5TRVJUIElOVE8gcHJvZHVjdF9wcmljZXMgKGRhdGEpIFZBTFVFUyAoJ3sibmFtZSI6ICJTbWFydHBob25lIiwgInByaWNlIjogOTk5Ljk5fScpLCAoJ3sibmFtZSI6ICJTbWFydHdhdGNoIiwgInByaWNlIjogNjk5LjQ5fScpIFJFVFVSTklORyBkYXRhOw%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-50\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">                  data\n<span class=\"hljs-comment\">-----------------------------------------<\/span>\n {\"name\": \"Smartphone\", \"price\": <span class=\"hljs-number\">999.99<\/span>}\n {\"name\": \"Smartwatch\", \"price\": <span class=\"hljs-number\">699.49<\/span>}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-50\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Sixth, retrieve the data from the <code>product_prices<\/code> table and cast it to the <code>product_info<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-51\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\"><span class=\"hljs-keyword\">SELECT<\/span>\n  data::product_info\n<span class=\"hljs-keyword\">FROM<\/span>\n  product_prices;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-51\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIGRhdGE6OnByb2R1Y3RfaW5mbyBGUk9NIHByb2R1Y3RfcHJpY2VzOw%3D%3D\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-52\" data-shcb-language-name=\"PostgreSQL SQL dialect and PL\/pgSQL\" data-shcb-language-slug=\"pgsql\"><span><code class=\"hljs language-pgsql\">        data\n<span class=\"hljs-comment\">---------------------<\/span>\n (Smartphone,<span class=\"hljs-number\">999.99<\/span>)\n (Smartwatch,<span class=\"hljs-number\">699.49<\/span>)<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-52\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PostgreSQL SQL dialect and PL\/pgSQL<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">pgsql<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='summary'>Summary <a href=\"#summary\" class=\"anchor\" id=\"summary\" title=\"Anchor for Summary\">#<\/a><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Use the <code>CAST(value AS type)<\/code> function or <code>value::type<\/code> operator to explicitly cast the value to another of a different type. <\/li>\n\n\n\n<li>Use the <code>CREATE CAST<\/code> statement to create a custom cast.<\/li>\n<\/ul>\n<div class=\"helpful-block-content\" data-title=\"\">\n\t<header>\n\t\t<div class=\"wth-question\">Was this tutorial helpful ?<\/div>\n\t\t<div class=\"wth-thumbs\">\n\t\t\t<button\n\t\t\t\tdata-post=\"2080\"\n\t\t\t\tdata-post-url=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-cast\/\"\n\t\t\t\tdata-post-title=\"PostgreSQL Cast\"\n\t\t\t\tdata-response=\"1\"\n\t\t\t\tclass=\"wth-btn-rounded wth-yes-btn\"\n\t\t\t>\n\t\t\t\t<svg\n\t\t\t\t\txmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n\t\t\t\t\tviewBox=\"0 0 24 24\"\n\t\t\t\t\tfill=\"none\"\n\t\t\t\t\tstroke=\"currentColor\"\n\t\t\t\t\tstroke-width=\"2\"\n\t\t\t\t\tstroke-linecap=\"round\"\n\t\t\t\t\tstroke-linejoin=\"round\"\n\t\t\t\t\tclass=\"feather feather-thumbs-up block w-full h-full\"\n\t\t\t\t>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M14 9V5a3 3 0 0 0-3-3l-4 9v11h11.28a2 2 0 0 0 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PostgreSQL Cast Overview # To convert a value of one data type to another, you use the CAST() function or cast operator (::). Here&#8217;s the syntax of the CAST() function: In [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":13,"menu_order":96,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-2080","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>PostgreSQL Cast<\/title>\n<meta name=\"description\" content=\"In this tutorial, you&#039;ll learn how to convert a value of one data type to another using the PostgreSQL CAST() function and operator.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-cast\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta 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