Smarter way to create unique indexes

This commit is contained in:
Michael 2017-01-15 23:30:43 +00:00
parent 47d04416b1
commit ced7cb6828
3 changed files with 89 additions and 17 deletions

View file

@ -176,15 +176,6 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
$definition = db_definition($charset);
}
// Ensure index conversion to unique removes duplicates
$sql_config = "SET session old_alter_table=1;";
if ($verbose) {
echo $sql_config."\n";
}
if ($action) {
$db->q($sql_config);
}
// MySQL >= 5.7.4 doesn't support the IGNORE keyword in ALTER TABLE statements
if ((version_compare($db->server_info(), '5.7.4') >= 0) AND
!(strpos($db->server_info(), 'MariaDB') !== false)) {
@ -204,6 +195,26 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
}
$is_new_table = True;
} else {
$is_unique = false;
$temp_name = $name;
foreach ($structure["indexes"] AS $indexname => $fieldnames) {
if (isset($database[$name]["indexes"][$indexname])) {
$current_index_definition = implode(",",$database[$name]["indexes"][$indexname]);
} else {
$current_index_definition = "__NOT_SET__";
}
$new_index_definition = implode(",",$fieldnames);
if ($current_index_definition != $new_index_definition) {
if ($fieldnames[0] == "UNIQUE") {
$is_unique = true;
if ($ignore == "") {
$temp_name = "temp-".$name;
}
}
}
}
/*
* Drop the index if it isn't present in the definition
* or the definition differ from current status
@ -219,7 +230,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
if ($current_index_definition != $new_index_definition && substr($indexname, 0, 6) != 'local_') {
$sql2=db_drop_index($indexname);
if ($sql3 == "") {
$sql3 = "ALTER".$ignore." TABLE `".$name."` ".$sql2;
$sql3 = "ALTER".$ignore." TABLE `".$temp_name."` ".$sql2;
} else {
$sql3 .= ", ".$sql2;
}
@ -230,7 +241,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
if (!isset($database[$name]["fields"][$fieldname])) {
$sql2=db_add_table_field($fieldname, $parameters);
if ($sql3 == "") {
$sql3 = "ALTER TABLE `".$name."` ".$sql2;
$sql3 = "ALTER TABLE `".$temp_name."` ".$sql2;
} else {
$sql3 .= ", ".$sql2;
}
@ -241,7 +252,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
if ($current_field_definition != $new_field_definition) {
$sql2=db_modify_table_field($fieldname, $parameters);
if ($sql3 == "") {
$sql3 = "ALTER TABLE `".$name."` ".$sql2;
$sql3 = "ALTER TABLE `".$temp_name."` ".$sql2;
} else {
$sql3 .= ", ".$sql2;
}
@ -268,7 +279,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
$sql2=db_create_index($indexname, $fieldnames);
if ($sql2 != "") {
if ($sql3 == "")
$sql3 = "ALTER" . $ignore . " TABLE `".$name."` ".$sql2;
$sql3 = "ALTER" . $ignore . " TABLE `".$temp_name."` ".$sql2;
else
$sql3 .= ", ".$sql2;
}
@ -278,13 +289,74 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
if ($sql3 != "") {
$sql3 .= ";";
if ($verbose)
if ($verbose) {
// Ensure index conversion to unique removes duplicates
if ($is_unique) {
if ($ignore != "") {
echo "SET session old_alter_table=1;\n";
} else {
echo "DROP TABLE IF EXISTS `".$temp_name."`;\n";
echo "CREATE TABLE `".$temp_name."` LIKE `".$name."`;\n";
}
}
echo $sql3."\n";
if ($is_unique) {
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";
}
}
}
if ($action) {
$r = @$db->q($sql3);
if (dbm::is_result($r))
// Ensure index conversion to unique removes duplicates
if ($is_unique) {
if ($ignore != "") {
$db->q("SET session old_alter_table=1;");
} else {
$r = $db->q("DROP TABLE IF EXISTS `".$temp_name."`;");
if (!dbm::is_result($r)) {
$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
return $errors;
}
$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($sql3);
if (!dbm::is_result($r))
$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
if ($is_unique) {
if ($ignore != "") {
$db->q("SET session old_alter_table=0;");
} else {
$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;
}
}
}
}
}
}

View file

@ -194,7 +194,7 @@ class dfrn {
`contact`.`name-date`, `contact`.`uri-date`, `contact`.`avatar-date`,
`contact`.`thumb`, `contact`.`dfrn-id`, `contact`.`self`,
`sign`.`signed_text`, `sign`.`signature`, `sign`.`signer`
FROM `item` USE INDEX (`uid_wall_changed`, `wall_uid_changed`) $sql_post_table
FROM `item` USE INDEX (`uid_wall_changed`) $sql_post_table
STRAIGHT_JOIN `contact` ON `contact`.`id` = `item`.`contact-id`
AND (NOT `contact`.`blocked` OR `contact`.`pending`)
LEFT JOIN `sign` ON `sign`.`iid` = `item`.`id`

View file

@ -239,7 +239,7 @@ function post_update_1206() {
logger("Start", LOGGER_DEBUG);
$r = q("SELECT `contact`.`id`, `contact`.`last-item`,
(SELECT MAX(`changed`) FROM `item` USE INDEX (`uid_wall_changed`, `wall_uid_changed`) WHERE `wall` AND `uid` = `user`.`uid`) AS `lastitem_date`
(SELECT MAX(`changed`) FROM `item` USE INDEX (`uid_wall_changed`) WHERE `wall` AND `uid` = `user`.`uid`) AS `lastitem_date`
FROM `user`
INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid` AND `contact`.`self`");