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Fix INSERT ... SELECT ... edge case in non-strict mode #285

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Merged
merged 1 commit into from
Nov 6, 2025
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Merged

Fix INSERT ... SELECT ... edge case in non-strict mode #285

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36 changes: 36 additions & 0 deletions tests/WP_SQLite_Driver_Tests.php
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Original file line number Diff line number Diff line change
Expand Up @@ -10526,6 +10526,42 @@ public function testCastValuesOnInsertInNonStrictMode(): void {
$this->assertQuery( 'DROP TABLE t' );
}

public function testCastNotNullValuesOnInsert(): void {
$this->assertQuery( 'CREATE TABLE t (value INT NOT NULL)' );

// Strict mode:
$this->assertQueryError( 'INSERT INTO t VALUES (NULL)', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQueryError( 'INSERT INTO t SET value = NULL', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQueryError( 'INSERT INTO t SELECT NULL', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQueryError( 'INSERT INTO t VALUES ((SELECT NULL))', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );

// Non-strict mode:
$this->assertQuery( "SET SESSION sql_mode = ''" );
$this->assertQueryError( 'INSERT INTO t VALUES (NULL)', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQueryError( 'INSERT INTO t SET value = NULL', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQuery( 'INSERT INTO t SELECT NULL' );
$this->assertSame( '0', $this->assertQuery( 'SELECT * FROM t' )[0]->value );
$this->assertQueryError( 'INSERT INTO t VALUES ((SELECT NULL))', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
}

public function testCastNotNullValuesOnUpdate(): void {
$this->assertQuery( 'CREATE TABLE t (value INT NOT NULL)' );
$this->assertQuery( 'INSERT INTO t VALUES (1)' );

// Strict mode:
$this->assertQueryError( 'UPDATE t SET value = NULL', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );
$this->assertQueryError( 'UPDATE t SET value = (SELECT NULL)', 'SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: t.value' );

// Non-strict mode:
$this->assertQuery( "SET SESSION sql_mode = ''" );
$this->assertQuery( 'UPDATE t SET value = NULL' );
$this->assertSame( '0', $this->assertQuery( 'SELECT * FROM t' )[0]->value );

$this->assertQuery( 'UPDATE t SET value = (SELECT NULL)' );
$this->assertSame( '0', $this->assertQuery( 'SELECT * FROM t' )[0]->value );
$this->assertQuery( 'DROP TABLE t' );
}

public function testCastValuesOnDuplicateKeyUpdate(): void {
$this->assertQuery( 'CREATE TABLE t (value TEXT UNIQUE)' );
$this->assertQuery( "INSERT INTO t VALUES ('test')" );
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18 changes: 17 additions & 1 deletion wp-includes/sqlite-ast/class-wp-sqlite-driver.php
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Expand Up @@ -4580,7 +4580,23 @@ function ( $column ) use ( $is_strict_mode, $insert_map ) {
// When a column value is included, we need to apply type casting.
$position = array_search( $column['COLUMN_NAME'], $insert_list, true );
$identifier = $this->quote_sqlite_identifier( $select_list[ $position ] );
$fragment .= $this->cast_value_for_saving( $column['DATA_TYPE'], $identifier );
$value = $this->cast_value_for_saving( $column['DATA_TYPE'], $identifier );

/*
* In MySQL non-STRICT mode, when inserting from a SELECT query:
*
* When a column is declared as NOT NULL, inserting a NULL value
* saves an IMPLICIT DEFAULT value instead. This behavior only
* applies to the INSERT ... SELECT syntax (not VALUES or SET).
*/
$is_insert_from_select = 'insertQueryExpression' === $node->rule_name;
if ( ! $is_strict_mode && $is_insert_from_select && 'NO' === $column['IS_NULLABLE'] ) {
$implicit_default = self::DATA_TYPE_IMPLICIT_DEFAULT_MAP[ $column['DATA_TYPE'] ] ?? null;
if ( null !== $implicit_default ) {
$value = sprintf( 'COALESCE(%s, %s)', $value, $this->connection->quote( $implicit_default ) );
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@adamziel adamziel Nov 6, 2025

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Is that SQLite coalesce? Will it give us the result we need?

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@JanJakes JanJakes Nov 6, 2025

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@adamziel Yes. There is a very similar logic for UPDATE SET ... = NULL already:

sqlite-database-integration/wp-includes/sqlite-ast/class-wp-sqlite-driver.php

Lines 4727 to 4738 in d982450

/*
* In MySQL non-STRICT mode, when a column is declared as NOT NULL,
* updating to a NULL value saves an IMPLICIT DEFAULT value instead.
* This behavior does not apply to ON DUPLICATE KEY UPDATE clauses.
*/
$is_on_duplicate_key_update = 'insertUpdateList' === $parent_node->rule_name;
if ( ! $is_strict_mode && ! $is_nullable && ! $is_on_duplicate_key_update ) {
$implicit_default = self::DATA_TYPE_IMPLICIT_DEFAULT_MAP[ $data_type ] ?? null;
if ( null !== $implicit_default ) {
$value = sprintf( 'COALESCE(%s, %s)', $value, $this->connection->quote( $implicit_default ) );
}
}

}
}
$fragment .= $value;
}
}

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