{"id":1136,"date":"2024-12-21T11:15:39","date_gmt":"2024-12-21T04:15:39","guid":{"rendered":"https:\/\/www.pgtutorial.com\/?page_id=1136"},"modified":"2025-01-05T20:28:40","modified_gmt":"2025-01-05T13:28:40","slug":"postgresql-first_value","status":"publish","type":"page","link":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/","title":{"rendered":"PostgreSQL FIRST_VALUE Window Function"},"content":{"rendered":"\n<p><strong>Summary<\/strong>: In this tutorial, you&#8217;ll learn how to use the PostgreSQL <code>FIRST_VALUE<\/code> window function to retrieve the first value in an ordered set of values.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='getting-started-with-the-first_value-window-function'>Getting Started with the FIRST_VALUE Window Function <a href=\"#getting-started-with-the-first_value-window-function\" class=\"anchor\" id=\"getting-started-with-the-first_value-window-function\" title=\"Anchor for Getting Started with the FIRST_VALUE Window Function\">#<\/a><\/h2>\n\n\n\n<p>The <code>FIRST_VALUE<\/code> is a window function that allows you to retrieve the first value in an ordered set of values.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id='syntax'>Syntax <a href=\"#syntax\" class=\"anchor\" id=\"syntax\" title=\"Anchor for Syntax\">#<\/a><\/h3>\n\n\n\n<p>Here&#8217;s the basic syntax of the <code>FIRST_VALUE<\/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\">FIRST_VALUE (expression) <span class=\"hljs-keyword\">OVER<\/span> (\n    &#91;<span class=\"hljs-keyword\">PARTITION<\/span> <span class=\"hljs-keyword\">BY<\/span> partition_expression]\n    &#91;<span class=\"hljs-keyword\">ORDER<\/span> <span class=\"hljs-keyword\">BY<\/span> sort_expression]\n)<\/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<h4 class=\"wp-block-heading\" id='parameters'>Parameters: <a href=\"#parameters\" class=\"anchor\" id=\"parameters\" title=\"Anchor for Parameters:\">#<\/a><\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>expression<\/code>: The column or expression from which you want to retrieve the first value.<\/li>\n\n\n\n<li><code>PARTITION BY<\/code>: Divides the result set into partitions by the <code>partition_expression<\/code>. The <code>partition_expression<\/code> can be one or more columns you want to use to divide the result set.<\/li>\n\n\n\n<li><code>ORDER BY<\/code>: Determines the order of rows within each partition using the <code>sort_expression<\/code>. The <code>sort_expression<\/code> can be one or more columns used for sorting the rows within each partition.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id='examples-of-postgresql-first_value-window-function'>Examples of PostgreSQL FIRST_VALUE Window Function <a href=\"#examples-of-postgresql-first_value-window-function\" class=\"anchor\" id=\"examples-of-postgresql-first_value-window-function\" title=\"Anchor for Examples of PostgreSQL FIRST_VALUE Window Function\">#<\/a><\/h2>\n\n\n\n<p>Let&#8217;s explore examples of using the <code>FIRST_VALUE<\/code> function with the <code>products<\/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 FIRST_VALUE Window Function - Sample Table\" class=\"wp-image-1051\"\/><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\" id='finding-the-first-product-with-the-highest-price'>Finding the First Product with the Highest Price <a href=\"#finding-the-first-product-with-the-highest-price\" class=\"anchor\" id=\"finding-the-first-product-with-the-highest-price\" title=\"Anchor for Finding the First Product with the Highest Price\">#<\/a><\/h3>\n\n\n\n<p>The following <code><a href=\"https:\/\/www.pgtutorial.com\/postgresql-tutorial\/postgresql-select\/\">SELECT<\/a><\/code> statement uses the <code>FIRST_VALUE<\/code> function to find the product with the highest price:<\/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\">SELECT<\/span>\n  product_name,\n  price,\n  FIRST_VALUE(product_name) <span class=\"hljs-keyword\">OVER<\/span> (\n    <span class=\"hljs-keyword\">ORDER<\/span> <span class=\"hljs-keyword\">BY<\/span>\n      price <span class=\"hljs-keyword\">DESC<\/span>\n  ) <span class=\"hljs-keyword\">AS<\/span> most_expensive_product\n<span class=\"hljs-keyword\">FROM<\/span>\n  products;<\/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><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIHByb2R1Y3RfbmFtZSwgcHJpY2UsIEZJUlNUX1ZBTFVFKHByb2R1Y3RfbmFtZSkgT1ZFUiAoIE9SREVSIEJZIHByaWNlIERFU0MgKSBBUyBtb3N0X2V4cGVuc2l2ZV9wcm9kdWN0IEZST00gcHJvZHVjdHM7\" 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-3\" data-shcb-language-name=\"plaintext\" data-shcb-language-slug=\"plaintext\"><span><code class=\"hljs language-plaintext\">        product_name        |  price  | most_expensive_product\n----------------------------+---------+-------------------------\n Samsung QN900C Neo QLED    | 2999.99 | Samsung QN900C Neo QLED\n LG G3 OLED                 | 2499.99 | Samsung QN900C Neo QLED\n Sony Bravia XR A95K        | 2499.99 | Samsung QN900C Neo QLED\n LG OLED TV C3              | 1999.99 | Samsung QN900C Neo QLED\n Samsung Galaxy Z Fold 5    | 1799.99 | Samsung QN900C Neo QLED\n Lenovo ThinkPad X1 Carbon  | 1599.99 | Samsung QN900C Neo QLED\n Dell XPS 15                | 1499.99 | Samsung QN900C Neo QLED\n HP Spectre x360            | 1399.99 | Samsung QN900C Neo QLED\n Microsoft Surface Laptop 5 | 1299.99 | Samsung QN900C Neo QLED\n Apple iPhone 15 Pro Max    | 1299.99 | Samsung QN900C Neo QLED\n Sony HT-A7000 Soundbar     | 1299.99 | Samsung QN900C Neo QLED\n Apple iMac 24\"             | 1299.99 | Samsung QN900C Neo QLED\n Apple iPhone 15            | 1099.99 | Samsung QN900C Neo QLED\n Apple iPad Pro 12.9        | 1099.99 | Samsung QN900C Neo QLED\n Samsung Galaxy S24         |  999.99 | Samsung QN900C Neo QLED\n Dell Inspiron 27           |  999.99 | Samsung QN900C Neo QLED\n Sony Xperia 1 VI           |  949.99 | Samsung QN900C Neo QLED\n Huawei Mate 60             |  899.99 | Samsung QN900C Neo QLED\n Xiaomi Mi 14               |  799.99 | Samsung QN900C Neo QLED\n Samsung Galaxy Tab S9      |  699.99 | Samsung QN900C Neo QLED\n Apple Watch Series 9       |  399.99 | Samsung QN900C Neo QLED\n Bose SoundLink Max         |  399.99 | Samsung QN900C Neo QLED\n Samsung Galaxy Watch 6     |  349.99 | Samsung QN900C Neo QLED\n Apple AirPods Pro 3        |  249.99 | Samsung QN900C Neo QLED\n Samsung Galaxy Buds Pro 2  |  199.99 | Samsung QN900C Neo QLED<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-3\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">plaintext<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">plaintext<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this example:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The <code>FIRST_VALUE<\/code> function does not use the <code>PARTITION BY<\/code> clause. Therefore, it treats the whole result set as a partition.<\/li>\n\n\n\n<li>The <code>ORDER BY price DESC<\/code> sorts the rows in the partition by price from high to low.<\/li>\n\n\n\n<li>The <code>FIRST_VALUE<\/code> retrieves the product name of the first product in the result set, which is the product with the highest price.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id='finding-the-most-expensive-product-in-each-category'>Finding the Most Expensive Product in Each Category <a href=\"#finding-the-most-expensive-product-in-each-category\" class=\"anchor\" id=\"finding-the-most-expensive-product-in-each-category\" title=\"Anchor for Finding the Most Expensive Product in Each Category\">#<\/a><\/h3>\n\n\n\n<p>The following <code>SELECT<\/code> statement uses the <code>FIRST_VALUE<\/code> function to find the product in each category with the highest price:<\/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\"><span class=\"hljs-keyword\">SELECT<\/span>\n    category_id,\n    product_name,\n    price,\n    FIRST_VALUE(product_name) <span class=\"hljs-keyword\">OVER<\/span> (\n        <span class=\"hljs-keyword\">PARTITION<\/span> <span class=\"hljs-keyword\">BY<\/span> category_id\n        <span class=\"hljs-keyword\">ORDER<\/span> <span class=\"hljs-keyword\">BY<\/span> price <span class=\"hljs-keyword\">DESC<\/span>\n    ) <span class=\"hljs-keyword\">AS<\/span> most_expensive_product\n<span class=\"hljs-keyword\">FROM<\/span>\n    products;<\/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><a href=\"https:\/\/www.pgtutorial.com\/playground\/?q=U0VMRUNUIGNhdGVnb3J5X2lkLCBwcm9kdWN0X25hbWUsIHByaWNlLCBGSVJTVF9WQUxVRShwcm9kdWN0X25hbWUpIE9WRVIgKCBQQVJUSVRJT04gQlkgY2F0ZWdvcnlfaWQgT1JERVIgQlkgcHJpY2UgREVTQyApIEFTIG1vc3RfZXhwZW5zaXZlX3Byb2R1Y3QgRlJPTSBwcm9kdWN0czs%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-5\" data-shcb-language-name=\"plaintext\" data-shcb-language-slug=\"plaintext\"><span><code class=\"hljs language-plaintext\"> category_id |        product_name        |  price  |  most_expensive_product\n-------------+----------------------------+---------+---------------------------\n           3 | Samsung Galaxy Z Fold 5    | 1799.99 | Samsung Galaxy Z Fold 5\n           3 | Apple iPhone 15 Pro Max    | 1299.99 | Samsung Galaxy Z Fold 5\n           3 | Apple iPhone 15            | 1099.99 | Samsung Galaxy Z Fold 5\n           3 | Samsung Galaxy S24         |  999.99 | Samsung Galaxy Z Fold 5\n           3 | Sony Xperia 1 VI           |  949.99 | Samsung Galaxy Z Fold 5\n           3 | Huawei Mate 60             |  899.99 | Samsung Galaxy Z Fold 5\n           3 | Xiaomi Mi 14               |  799.99 | Samsung Galaxy Z Fold 5\n           4 | Apple iPad Pro 12.9        | 1099.99 | Apple iPad Pro 12.9\n           4 | Samsung Galaxy Tab S9      |  699.99 | Apple iPad Pro 12.9\n           5 | Apple AirPods Pro 3        |  249.99 | Apple AirPods Pro 3\n           5 | Samsung Galaxy Buds Pro 2  |  199.99 | Apple AirPods Pro 3\n           6 | Apple Watch Series 9       |  399.99 | Apple Watch Series 9\n           6 | Samsung Galaxy Watch 6     |  349.99 | Apple Watch Series 9\n           8 | Samsung QN900C Neo QLED    | 2999.99 | Samsung QN900C Neo QLED\n           8 | Sony Bravia XR A95K        | 2499.99 | Samsung QN900C Neo QLED\n           8 | LG G3 OLED                 | 2499.99 | Samsung QN900C Neo QLED\n           8 | LG OLED TV C3              | 1999.99 | Samsung QN900C Neo QLED\n           9 | Sony HT-A7000 Soundbar     | 1299.99 | Sony HT-A7000 Soundbar\n           9 | Bose SoundLink Max         |  399.99 | Sony HT-A7000 Soundbar\n          11 | Lenovo ThinkPad X1 Carbon  | 1599.99 | Lenovo ThinkPad X1 Carbon\n          11 | Dell XPS 15                | 1499.99 | Lenovo ThinkPad X1 Carbon\n          11 | HP Spectre x360            | 1399.99 | Lenovo ThinkPad X1 Carbon\n          11 | Microsoft Surface Laptop 5 | 1299.99 | Lenovo ThinkPad X1 Carbon\n          12 | Apple iMac 24\"             | 1299.99 | Apple iMac 24\"\n          12 | Dell Inspiron 27           |  999.99 | Apple iMac 24\"<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-5\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">plaintext<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">plaintext<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this example:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The <code>PARTITION BY<\/code> clause divides the rows from the <code>products<\/code> table into partitions by <code>category_id<\/code>.<\/li>\n\n\n\n<li>The <code>ORDER BY<\/code> clause sorts the products in each partition by the price in descending order.<\/li>\n\n\n\n<li>The <code>FIRST_VALUE<\/code> function retrieves the name of the first product in each category based on the highest price.<\/li>\n<\/ul>\n\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 PostgreSQL <code>FIRST_VALUE<\/code> function to get the first value in a set of values.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id='quiz'>Quiz <a href=\"#quiz\" class=\"anchor\" id=\"quiz\" title=\"Anchor for Quiz\">#<\/a><\/h2>\n\n\n\n<iframe loading=\"lazy\"\n  name=\"quiz\"\n  src=\"\/quiz\/?quiz=first_value\"\n  height=\"700\"\n  width=\"600\"\n  class=\"iframe\"\n><\/iframe>\n\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=\"1136\"\n\t\t\t\tdata-post-url=\"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/\"\n\t\t\t\tdata-post-title=\"PostgreSQL FIRST_VALUE Window Function\"\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 2-1.7l1.38-9a2 2 0 0 0-2-2.3zM7 22H4a2 2 0 0 1-2-2v-7a2 2 0 0 1 2-2h3\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> Yes <\/span>\n\t\t\t<\/button>\n\n\t\t\t<button\n\t\t\t\tdata-response=\"0\"\n\t\t\t\tdata-post=\"1136\"\n\t\t\t\tdata-post-url=\"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/\"\n\t\t\t\tdata-post-title=\"PostgreSQL FIRST_VALUE Window Function\"\n\t\t\t\tclass=\"wth-btn-rounded wth-no-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>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M10 15v4a3 3 0 0 0 3 3l4-9V2H5.72a2 2 0 0 0-2 1.7l-1.38 9a2 2 0 0 0 2 2.3zm7-13h2.67A2.31 2.31 0 0 1 22 4v7a2.31 2.31 0 0 1-2.33 2H17\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> No <\/span>\n\t\t\t<\/button>\n\t\t<\/div>\n\t<\/header>\n\n\t<div class=\"wth-form hidden\">\n\t\t<div class=\"wth-form-wrapper\">\n\t\t\t<div class=\"wth-title\"><\/div>\n\t\t\t\n\t\t\t<textarea class=\"wth-message\"><\/textarea>\n\n\t\t\t<button class=\"btn btn-primary wth-btn-submit\">Send<\/button>\n\t\t\t<button class=\"btn wth-btn-cancel\">Cancel<\/button>\n\t\t\n\t\t<\/div>\n\t<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Summary: In this tutorial, you&#8217;ll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values. Getting Started with the FIRST_VALUE Window Function # The FIRST_VALUE is a window function that allows you to retrieve the first value in an ordered set of values. Syntax # [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1072,"menu_order":6,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1136","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 FIRST_VALUE Window Function<\/title>\n<meta name=\"description\" content=\"In this tutorial, you&#039;ll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.\" \/>\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-window-functions\/postgresql-first_value\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"PostgreSQL FIRST_VALUE Window Function\" \/>\n<meta property=\"og:description\" content=\"In this tutorial, you&#039;ll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/\" \/>\n<meta property=\"og:site_name\" content=\"PostgreSQL Tutorial\" \/>\n<meta property=\"article:modified_time\" content=\"2025-01-05T13:28:40+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png\" \/>\n\t<meta property=\"og:image:width\" content=\"159\" \/>\n\t<meta property=\"og:image:height\" content=\"254\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/\",\"url\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/\",\"name\":\"PostgreSQL FIRST_VALUE Window Function\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.pgtutorial.com\\\/wp-content\\\/uploads\\\/2024\\\/12\\\/products.png\",\"datePublished\":\"2024-12-21T04:15:39+00:00\",\"dateModified\":\"2025-01-05T13:28:40+00:00\",\"description\":\"In this tutorial, you'll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.pgtutorial.com\\\/wp-content\\\/uploads\\\/2024\\\/12\\\/products.png\",\"contentUrl\":\"https:\\\/\\\/www.pgtutorial.com\\\/wp-content\\\/uploads\\\/2024\\\/12\\\/products.png\",\"width\":159,\"height\":254,\"caption\":\"PostgreSQL Expression Index\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/postgresql-first_value\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.pgtutorial.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"PostgreSQL Window Functions\",\"item\":\"https:\\\/\\\/www.pgtutorial.com\\\/postgresql-window-functions\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"PostgreSQL FIRST_VALUE Window Function\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.pgtutorial.com\\\/#website\",\"url\":\"https:\\\/\\\/www.pgtutorial.com\\\/\",\"name\":\"PostgreSQL Tutorial\",\"description\":\"Learn PostgreSQL from Scratch\",\"alternateName\":\"PostgreSQL\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.pgtutorial.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"PostgreSQL FIRST_VALUE Window Function","description":"In this tutorial, you'll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/","og_locale":"en_US","og_type":"article","og_title":"PostgreSQL FIRST_VALUE Window Function","og_description":"In this tutorial, you'll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.","og_url":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/","og_site_name":"PostgreSQL Tutorial","article_modified_time":"2025-01-05T13:28:40+00:00","og_image":[{"width":159,"height":254,"url":"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png","type":"image\/png"}],"twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/","url":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/","name":"PostgreSQL FIRST_VALUE Window Function","isPartOf":{"@id":"https:\/\/www.pgtutorial.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/#primaryimage"},"image":{"@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/#primaryimage"},"thumbnailUrl":"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png","datePublished":"2024-12-21T04:15:39+00:00","dateModified":"2025-01-05T13:28:40+00:00","description":"In this tutorial, you'll learn how to use the PostgreSQL FIRST_VALUE window function to retrieve the first value in an ordered set of values.","breadcrumb":{"@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/#primaryimage","url":"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png","contentUrl":"https:\/\/www.pgtutorial.com\/wp-content\/uploads\/2024\/12\/products.png","width":159,"height":254,"caption":"PostgreSQL Expression Index"},{"@type":"BreadcrumbList","@id":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/postgresql-first_value\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.pgtutorial.com\/"},{"@type":"ListItem","position":2,"name":"PostgreSQL Window Functions","item":"https:\/\/www.pgtutorial.com\/postgresql-window-functions\/"},{"@type":"ListItem","position":3,"name":"PostgreSQL FIRST_VALUE Window Function"}]},{"@type":"WebSite","@id":"https:\/\/www.pgtutorial.com\/#website","url":"https:\/\/www.pgtutorial.com\/","name":"PostgreSQL Tutorial","description":"Learn PostgreSQL from Scratch","alternateName":"PostgreSQL","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.pgtutorial.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"}]}},"_links":{"self":[{"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/pages\/1136","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/comments?post=1136"}],"version-history":[{"count":6,"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/pages\/1136\/revisions"}],"predecessor-version":[{"id":1470,"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/pages\/1136\/revisions\/1470"}],"up":[{"embeddable":true,"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/pages\/1072"}],"wp:attachment":[{"href":"https:\/\/www.pgtutorial.com\/wp-json\/wp\/v2\/media?parent=1136"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}