Addind unique indexes should now work with every MySQL flavour

diff --git a/include/dbstructure.php b/include/dbstructure.php
index 346920ab0702c0f4db80cf6891cccaffe55ec414..b17ef8ed8cafdc1460be1757bb11fb4810c34ea0 100644 (file)
--- a/include/dbstructure.php
+++ b/include/dbstructure.php
@@ -187,7 +187,8 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
        // Compare it
        foreach ($definition AS $name => $structure) {
                $is_new_table = False;
-               $sql3="";
+               $group_by = "";
+               $sql3 = "";
                if (!isset($database[$name])) {
                        $r = db_create_table($name, $structure["fields"], $charset, $verbose, $action, $structure['indexes']);
                        if (!dbm::is_result($r)) {
@@ -208,10 +209,9 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
                                if ($current_index_definition != $new_index_definition) {
                                        if ($fieldnames[0] == "UNIQUE") {
                                                $is_unique = true;
-                                               // Deactivated. See below for the reason
-                                               //if ($ignore == "") {
-                                               //      $temp_name = "temp-".$name;
-                                               //}
+                                               if ($ignore == "") {
+                                                       $temp_name = "temp-".$name;
+                                               }
                                        }
                                }
                        }
@@ -277,7 +277,12 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
                                }
                                $new_index_definition = implode(",",$fieldnames);
                                if ($current_index_definition != $new_index_definition) {
-                                       $sql2=db_create_index($indexname, $fieldnames);
+                                       $sql2 = db_create_index($indexname, $fieldnames);
+
+                                       // Fetch the "group by" fields for unique indexes
+                                       if ($fieldnames[0] == "UNIQUE") {
+                                               $group_by = db_group_by($indexname, $fieldnames);
+                                       }
                                        if ($sql2 != "") {
                                                if ($sql3 == "")
                                                        $sql3 = "ALTER" . $ignore . " TABLE `".$temp_name."` ".$sql2;
@@ -293,44 +298,38 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
                        if ($verbose) {
                                // Ensure index conversion to unique removes duplicates
                                if ($is_unique) {
-                                       // By now the alternative is commented out.
-                                       // This is a preparation for the time when we found a good SQL routine.
-                                       //if ($ignore != "") {
+                                       if ($ignore != "") {
                                                echo "SET session old_alter_table=1;\n";
-                                       //} else {
-                                       //      echo "CREATE TABLE `".$temp_name."` LIKE `".$name."`;\n";
-                                       //}
+                                       } else {
+                                               echo "CREATE TABLE `".$temp_name."` LIKE `".$name."`;\n";
+                                       }
                                }
 
                                echo $sql3."\n";
 
                                if ($is_unique) {
-                                       // By now the alternative is commented out.
-                                       // This is a preparation for the time when we found a good SQL routine.
-                                       //if ($ignore != "") {
+                                       if ($ignore != "") {
                                                echo "SET session old_alter_table=0;\n";
-                                       //} else {
-                                       //      echo "INSERT IGNORE INTO `".$temp_name."` SELECT * FROM `".$name."`;\n";
-                                       //      echo "DROP TABLE `".$name."`;\n";
-                                       //      echo "RENAME TABLE `".$temp_name."` TO `".$name."`;\n";
-                                       //}
+                                       } else {
+                                               echo "INSERT INTO `".$temp_name."` SELECT * FROM `".$name."`".$group_by.";\n";
+                                               echo "DROP TABLE `".$name."`;\n";
+                                               echo "RENAME TABLE `".$temp_name."` TO `".$name."`;\n";
+                                       }
                                }
                        }
 
                        if ($action) {
                                // Ensure index conversion to unique removes duplicates
                                if ($is_unique) {
-                                       // By now the alternative is commented out.
-                                       // This is a preparation for the time when we found a good SQL routine.
-                                       //if ($ignore != "") {
+                                       if ($ignore != "") {
                                                $db->q("SET session old_alter_table=1;");
-                                       //} else {
-                                       //      $r = $db->q("CREATE TABLE `".$temp_name."` LIKE `".$name."`;");
-                                       //      if (!dbm::is_result($r)) {
-                                       //              $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
-                                       //              return $errors;
-                                       //      }
-                                       //}
+                                       } else {
+                                               $r = $db->q("CREATE TABLE `".$temp_name."` LIKE `".$name."`;");
+                                               if (!dbm::is_result($r)) {
+                                                       $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+                                                       return $errors;
+                                               }
+                                       }
                                }
 
                                $r = @$db->q($sql3);
@@ -338,28 +337,25 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
                                        $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
 
                                if ($is_unique) {
-                                       // By now the alternative is commented out.
-                                       // This is a preparation for the time when we found a good SQL routine.
-                                       //if ($ignore != "") {
+                                       if ($ignore != "") {
                                                $db->q("SET session old_alter_table=0;");
-                                       //} else {
-                                       //      We have to check if "INSERT IGNORE" will work on newer MySQL versions
-                                       //      $r = $db->q("INSERT IGNORE INTO `".$temp_name."` SELECT * FROM `".$name."`;");
-                                       //      if (!dbm::is_result($r)) {
-                                       //              $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
-                                       //              return $errors;
-                                       //      }
-                                       //      $r = $db->q("DROP TABLE `".$name."`;");
-                                       //      if (!dbm::is_result($r)) {
-                                       //              $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
-                                       //              return $errors;
-                                       //      }
-                                       //      $r = $db->q("RENAME TABLE `".$temp_name."` TO `".$name."`;");
-                                       //      if (!dbm::is_result($r)) {
-                                       //              $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
-                                       //              return $errors;
-                                       //      }
-                                       //}
+                                       } else {
+                                               $r = $db->q("INSERT INTO `".$temp_name."` SELECT * FROM `".$name."`".$group_by.";");
+                                               if (!dbm::is_result($r)) {
+                                                       $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+                                                       return $errors;
+                                               }
+                                               $r = $db->q("DROP TABLE `".$name."`;");
+                                               if (!dbm::is_result($r)) {
+                                                       $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+                                                       return $errors;
+                                               }
+                                               $r = $db->q("RENAME TABLE `".$temp_name."` TO `".$name."`;");
+                                               if (!dbm::is_result($r)) {
+                                                       $errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+                                                       return $errors;
+                                               }
+                                       }
                                }
                        }
                }
@@ -477,6 +473,30 @@ function db_create_index($indexname, $fieldnames, $method="ADD") {
        return($sql);
 }
 
+function db_group_by($indexname, $fieldnames) {
+
+       if ($fieldnames[0] != "UNIQUE") {
+               return "";
+       }
+
+       array_shift($fieldnames);
+
+       $names = "";
+       foreach ($fieldnames AS $fieldname) {
+               if ($names != "")
+                       $names .= ",";
+
+               if (preg_match('|(.+)\((\d+)\)|', $fieldname, $matches)) {
+                       $names .= "`".dbesc($matches[1])."`";
+               } else {
+                       $names .= "`".dbesc($fieldname)."`";
+               }
+       }
+
+       $sql = sprintf(" GROUP BY %s", $names);
+       return $sql;
+}
+
 function db_index_suffix($charset, $reduce = 0) {
        if ($charset != "utf8mb4") {
                return "";