Added tests and more safe codding

chernser · chernser · commit 2790aebd14a0 · 2026-03-16T15:15:12.000-07:00
diff --git a/jdbc-v2/src/main/java/com/clickhouse/jdbc/StatementImpl.java b/jdbc-v2/src/main/java/com/clickhouse/jdbc/StatementImpl.java
@@ -190,9 +190,18 @@ protected ResultSetImpl executeQueryImpl(String sql, QuerySettings settings) thr
                     // Best effort: leave writtenRows as 0 if we can't obtain it.
                 }
                 this.currentUpdateCount = (int) Math.min(writtenRows, Integer.MAX_VALUE);
-                reader.close();
-                response.close();
-                onResultSetClosed(null); // no more result sets left - close statement.
+                try {
+                    reader.close();
+                } catch (Exception closeEx) {
+                    LOG.warn("Failed to close reader when schema is null", closeEx);
+                } finally {
+                    try {
+                        response.close();
+                    } catch (Exception closeRespEx) {
+                        LOG.warn("Failed to close response when schema is null", closeRespEx);
+                    }
+                }
+                onResultSetClosed(null);
                 return null;
             }
             return new ResultSetImpl(this, response, reader, this::handleSocketTimeoutException);
diff --git a/jdbc-v2/src/test/java/com/clickhouse/jdbc/PreparedStatementTest.java b/jdbc-v2/src/test/java/com/clickhouse/jdbc/PreparedStatementTest.java
@@ -1810,6 +1810,26 @@ public void testUnknownStatementTest() throws Exception {
                     }
                 }
             }
+
+            // No-ResultSet path: DDL should not produce a ResultSet
+            String tmpTable = "tmp_no_result_" + RandomStringUtils.randomAlphanumeric(8);
+            // PreparedStatement: execute() should return false, executeQuery() should throw
+            try (PreparedStatement stmt = conn.prepareStatement(
+                    "CREATE TEMPORARY TABLE " + tmpTable + " (x Int32)")) {
+                Assert.assertFalse(stmt.execute(), "DDL should not produce a ResultSet");
+                Assert.assertNull(stmt.getResultSet(), "ResultSet should be null for DDL");
+                assertThrows(SQLException.class, stmt::executeQuery);
+            }
+            // Statement: execute() should return false, executeQuery() should throw
+            String tmpTable2 = "tmp_no_result_" + RandomStringUtils.randomAlphanumeric(8);
+            try (Statement stmt = conn.createStatement()) {
+                Assert.assertFalse(
+                        stmt.execute("CREATE TEMPORARY TABLE " + tmpTable2 + " (x Int32)"),
+                        "DDL should not produce a ResultSet");
+                Assert.assertNull(stmt.getResultSet(), "ResultSet should be null for DDL");
+                assertThrows(SQLException.class,
+                        () -> stmt.executeQuery("CREATE TEMPORARY TABLE " + tmpTable2 + " (x Int32)"));
+            }
         }
     }
 }
diff --git a/jdbc-v2/src/test/java/com/clickhouse/jdbc/StatementTest.java b/jdbc-v2/src/test/java/com/clickhouse/jdbc/StatementTest.java
@@ -1342,12 +1342,17 @@ public void testUnknownStatementTest(String parserName) throws Exception {
                 stmt.execute("DROP TABLE IF EXISTS test_unknown_statement_test");
                 stmt.execute("CREATE TABLE test_unknown_statement_test (v Int32) Engine MergeTree ORDER BY ()");
 
-                stmt.execute("INSERT INTO test_unknown_statement_test VALUES (1);");
+                // INSERT via execute(...) must not produce a ResultSet and should return false
+                boolean hasResultSet = stmt.execute("INSERT INTO test_unknown_statement_test VALUES (1);");
+                assertFalse(hasResultSet);
                 assertEquals(stmt.getUpdateCount(), 1);
 
                 stmt.executeUpdate("INSERT INTO test_unknown_statement_test VALUES (2);");
                 assertEquals(stmt.getUpdateCount(), 1);
 
+                assertThrows(SQLException.class,
+                        () -> stmt.executeQuery("INSERT INTO test_unknown_statement_test VALUES (3);"));
+
             }
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -1810,6 +1810,26 @@ public void testUnknownStatementTest() throws Exception {`
`1810`	`1810`	`}`
`1811`	`1811`	`}`
`1812`	`1812`	`}`
	`1813`	`+`
	`1814`	`+ // No-ResultSet path: DDL should not produce a ResultSet`
	`1815`	`+ String tmpTable = "tmp_no_result_" + RandomStringUtils.randomAlphanumeric(8);`
	`1816`	`+ // PreparedStatement: execute() should return false, executeQuery() should throw`
	`1817`	`+ try (PreparedStatement stmt = conn.prepareStatement(`
	`1818`	`+ "CREATE TEMPORARY TABLE " + tmpTable + " (x Int32)")) {`
	`1819`	`+ Assert.assertFalse(stmt.execute(), "DDL should not produce a ResultSet");`
	`1820`	`+ Assert.assertNull(stmt.getResultSet(), "ResultSet should be null for DDL");`
	`1821`	`+ assertThrows(SQLException.class, stmt::executeQuery);`
	`1822`	`+ }`
	`1823`	`+ // Statement: execute() should return false, executeQuery() should throw`
	`1824`	`+ String tmpTable2 = "tmp_no_result_" + RandomStringUtils.randomAlphanumeric(8);`
	`1825`	`+ try (Statement stmt = conn.createStatement()) {`
	`1826`	`+ Assert.assertFalse(`
	`1827`	`+ stmt.execute("CREATE TEMPORARY TABLE " + tmpTable2 + " (x Int32)"),`
	`1828`	`+ "DDL should not produce a ResultSet");`
	`1829`	`+ Assert.assertNull(stmt.getResultSet(), "ResultSet should be null for DDL");`
	`1830`	`+ assertThrows(SQLException.class,`
	`1831`	`+ () -> stmt.executeQuery("CREATE TEMPORARY TABLE " + tmpTable2 + " (x Int32)"));`
	`1832`	`+ }`
`1813`	`1833`	`}`
`1814`	`1834`	`}`
`1815`	`1835`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1342,12 +1342,17 @@ public void testUnknownStatementTest(String parserName) throws Exception {`
`1342`	`1342`	`stmt.execute("DROP TABLE IF EXISTS test_unknown_statement_test");`
`1343`	`1343`	`stmt.execute("CREATE TABLE test_unknown_statement_test (v Int32) Engine MergeTree ORDER BY ()");`
`1344`	`1344`
`1345`		`- stmt.execute("INSERT INTO test_unknown_statement_test VALUES (1);");`
	`1345`	`+ // INSERT via execute(...) must not produce a ResultSet and should return false`
	`1346`	`+ boolean hasResultSet = stmt.execute("INSERT INTO test_unknown_statement_test VALUES (1);");`
	`1347`	`+ assertFalse(hasResultSet);`
`1346`	`1348`	`assertEquals(stmt.getUpdateCount(), 1);`
`1347`	`1349`
`1348`	`1350`	`stmt.executeUpdate("INSERT INTO test_unknown_statement_test VALUES (2);");`
`1349`	`1351`	`assertEquals(stmt.getUpdateCount(), 1);`
`1350`	`1352`
	`1353`	`+ assertThrows(SQLException.class,`
	`1354`	`+ () -> stmt.executeQuery("INSERT INTO test_unknown_statement_test VALUES (3);"));`
	`1355`	`+`
`1351`	`1356`	`}`
`1352`	`1357`	`}`
`1353`	`1358`	`}`