#74997 by dww, add db_table_exists()

includes/database.mysql.inc

@@ -364,6 +364,13 @@ function db_unlock_tables() {
   db_query('UNLOCK TABLES');
 }
 
+/**
+ * Check if a table exists.
+ */
+function db_table_exists($table) {
+  return db_num_rows(db_query("SHOW TABLES LIKE '{" . db_escape_table($table) . "}'"));
+}
+
 /**
  * @} End of "ingroup database".
  */

includes/database.mysqli.inc

@@ -366,6 +366,13 @@ function db_unlock_tables() {
   db_query('UNLOCK TABLES');
 }
 
+/**
+ * Check if a table exists.
+ */
+function db_table_exists($table) {
+  return db_num_rows(db_query("SHOW TABLES LIKE '{" . db_escape_table($table) . "}'"));
+}
+
 /**
  * @} End of "ingroup database".
  */

includes/database.pgsql.inc

@@ -343,6 +343,13 @@ function db_unlock_tables() {
   db_query('COMMIT');
 }
 
+/**
+ * Check if a table exists.
+ */
+function db_table_exists($table) {
+  return db_num_rows(db_query("SELECT relname FROM pg_class WHERE relname = '{" . db_escape_table($table) . "}'"));
+}
+
 /**
  * Verify if the database is set up correctly.
  */