Implement DROP INDEX statement

Author: JanJakes

tests/WP_SQLite_Driver_Tests.php

@@ -5514,4 +5514,17 @@ public function testCreateIndexWithDuplicateName(): void {
 
 		$this->assertQuery( 'CREATE INDEX idx_value ON t (val2)' );
 	}
+
+	public function testDropIndex(): void {
+		$this->assertQuery( 'CREATE TABLE t (id INT PRIMARY KEY, val_unique INT UNIQUE, val_index INT)' );
+		$this->assertQuery( 'CREATE INDEX idx_val_index ON t (val_index)' );
+
+		$result = $this->assertQuery( 'SHOW INDEX FROM t' );
+		$this->assertCount( 3, $result );
+		$this->assertEquals( 'PRIMARY', $result[0]->Key_name );
+		$this->assertEquals( 'val_unique', $result[1]->Key_name );
+		$this->assertEquals( 'idx_val_index', $result[2]->Key_name );
+
+		$this->assertQuery( 'DROP INDEX idx_val_index ON t' );
+	}
 }

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

@@ -912,6 +912,9 @@ private function execute_mysql_query( WP_Parser_Node $node ): void {
 					case 'dropTable':
 						$this->execute_drop_table_statement( $node );
 						break;
+					case 'dropIndex':
+						$this->execute_drop_index_statement( $node );
+						break;
 					default:
 						$query = $this->translate( $node );
 						$this->execute_sqlite_query( $query );
@@ -1511,6 +1514,32 @@ private function execute_create_index_statement( WP_Parser_Node $node ): void {
 		);
 	}
 
+	/**
+	 * Translate and execute a MySQL DROP INDEX statement in SQLite.
+	 *
+	 * @param  WP_Parser_Node $node       The "dropStatement" AST node with "dropIndex" child.
+	 * @throws WP_SQLite_Driver_Exception When the query execution fails.
+	 */
+	private function execute_drop_index_statement( WP_Parser_Node $node ): void {
+		$this->information_schema_builder->record_drop_index( $node );
+
+		$drop_index = $node->get_first_child_node( 'dropIndex' );
+		$table_name = $this->unquote_sqlite_identifier(
+			$this->translate( $drop_index->get_first_child_node( 'tableRef' ) )
+		);
+		$index_name = $this->unquote_sqlite_identifier(
+			$this->translate( $drop_index->get_first_child_node( 'indexRef' ) )
+		);
+
+		$sqlite_index_name = $this->get_sqlite_index_name( $table_name, $index_name );
+		$this->execute_sqlite_query(
+			sprintf(
+				'DROP INDEX %s',
+				$this->quote_sqlite_identifier( $sqlite_index_name )
+			)
+		);
+	}
+
 	/**
 	 * Translate and execute a MySQL SHOW statement in SQLite.
 	 *

wp-includes/sqlite-ast/class-wp-sqlite-information-schema-builder.php

@@ -584,7 +584,7 @@ public function record_alter_table( WP_Parser_Node $node ): void {
 				// DROP INDEX
 				if ( $action->has_child_node( 'keyOrIndex' ) ) {
 					$name = $this->get_value( $action->get_first_child_node( 'indexRef' ) );
-					$this->record_drop_index( $table_is_temporary, $table_name, $name );
+					$this->record_drop_index_data( $table_is_temporary, $table_name, $name );
 					continue;
 				}
 			}
@@ -653,6 +653,19 @@ public function record_create_index( WP_Parser_Node $node ): void {
 		$this->record_add_index( $table_is_temporary, $table_name, $create_index );
 	}
 
+	/**
+	 * Analyze DROP INDEX definition and record data in the information schema.
+	 *
+	 * @param WP_Parser_Node $node The "dropStatement" AST node with "dropIndex" child.
+	 */
+	public function record_drop_index( WP_Parser_Node $node ): void {
+		$drop_index         = $node->get_first_child_node( 'dropIndex' );
+		$table_name         = $this->get_value( $drop_index->get_first_child_node( 'tableRef' ) );
+		$index_name         = $this->get_value( $drop_index->get_first_child_node( 'indexRef' ) );
+		$table_is_temporary = $this->temporary_table_exists( $table_name );
+		$this->record_drop_index_data( $table_is_temporary, $table_name, $index_name );
+	}
+
 	/**
 	 * Analyze ADD COLUMN definition and record data in the information schema.
 	 *
@@ -1006,7 +1019,7 @@ private function record_add_index(
 	 * @param string $table_name         The table name.
 	 * @param string $index_name         The index name.
 	 */
-	private function record_drop_index(
+	private function record_drop_index_data(
 		bool $table_is_temporary,
 		string $table_name,
 		string $index_name