MySQL: Speed up displaying tables in large databases (bug #700)

diff --git a/adminer/drivers/mysql.inc.php b/adminer/drivers/mysql.inc.php
index 563d1ffe56906946bb35aa4b3118a063cac0c389..dea561fe5400513b988076334d302cd3392869d8 100644 (file)
--- a/adminer/drivers/mysql.inc.php
+++ b/adminer/drivers/mysql.inc.php
@@ -583,18 +583,24 @@ if (!defined("DRIVER")) {
        * @return array array($name => array("db" => , "ns" => , "table" => , "source" => array(), "target" => array(), "on_delete" => , "on_update" => ))
        */
        function foreign_keys($table) {
+               global $connection, $on_actions;
+               static $pattern = '(?:`(?:[^`]|``)+`|(?:"(?:[^"]|"")+"))';
                $return = array();
-               foreach (get_rows("SELECT * FROM information_schema.REFERENTIAL_CONSTRAINTS WHERE CONSTRAINT_SCHEMA = DATABASE() AND TABLE_NAME = " . q($table)) as $row) {
-                       $columns = get_key_vals("SELECT COLUMN_NAME, REFERENCED_COLUMN_NAME FROM information_schema.KEY_COLUMN_USAGE WHERE CONSTRAINT_SCHEMA = DATABASE() AND CONSTRAINT_NAME = " . q($row["CONSTRAINT_NAME"]) . " ORDER BY ORDINAL_POSITION");
-                       $db = $row["UNIQUE_CONSTRAINT_SCHEMA"];
-                       $return[$row["CONSTRAINT_NAME"]] = array(
-                               "db" => ($db == DB ? "" : $db),
-                               "table" => $row["REFERENCED_TABLE_NAME"],
-                               "source" => array_keys($columns),
-                               "target" => array_values($columns),
-                               "on_delete" => $row["DELETE_RULE"],
-                               "on_update" => $row["UPDATE_RULE"],
-                       );
+               $create_table = $connection->result("SHOW CREATE TABLE " . table($table), 1);
+               if ($create_table) {
+                       preg_match_all("~CONSTRAINT ($pattern) FOREIGN KEY ?\\(((?:$pattern,? ?)+)\\) REFERENCES ($pattern)(?:\\.($pattern))? \\(((?:$pattern,? ?)+)\\)(?: ON DELETE ($on_actions))?(?: ON UPDATE ($on_actions))?~", $create_table, $matches, PREG_SET_ORDER);
+                       foreach ($matches as $match) {
+                               preg_match_all("~$pattern~", $match[2], $source);
+                               preg_match_all("~$pattern~", $match[5], $target);
+                               $return[idf_unescape($match[1])] = array(
+                                       "db" => idf_unescape($match[4] != "" ? $match[3] : $match[4]),
+                                       "table" => idf_unescape($match[4] != "" ? $match[4] : $match[3]),
+                                       "source" => array_map('idf_unescape', $source[0]),
+                                       "target" => array_map('idf_unescape', $target[0]),
+                                       "on_delete" => ($match[6] ? $match[6] : "RESTRICT"),
+                                       "on_update" => ($match[7] ? $match[7] : "RESTRICT"),
+                               );
+                       }
                }
                return $return;
        }

diff --git a/changes.txt b/changes.txt
index 124ac4f7b9ffaccb203c532ffa0d274b335e71b5..933d42fd1651c03f662bbd6bd50eeebfbfcb1338 100644 (file)
--- a/changes.txt
+++ b/changes.txt
@@ -1,4 +1,5 @@
 Adminer 4.7.3-dev:
+MySQL: Speed up displaying tables in large databases (bug #700)
 MySQL: Skip editing generated columns
 SQLite: Quote strings stored in integer columns in export (bug #696)
 
@@ -8,7 +9,7 @@ Stretch footer over the whole table width (bug #624)
 Allow overwriting tables when copying them
 Fix displaying SQL command after Save and continue edit
 Cache busting for adminer.css
-MySQL: Fix displaying multi-columns foreign keys (bug #675)
+MySQL: Fix displaying multi-columns foreign keys (bug #675, regression from 4.7.0)
 MySQL: Fix creating users and changing password in MySQL 8 (bug #663)
 MySQL: Pass SRID to GeomFromText
 PostgreSQL: Fix setting column comments on new table