maxdb_rollback
maxdb::rollback
(PECL maxdb >= 1.0)
maxdb_rollback -- maxdb::rollback — Rolls back current transaction
说明
过程化风格
maxdb_rollback (
resource
$link
) :
bool
面向对象风格
maxdb::rollback (
void ) :
bool
Rollbacks the current transaction for the database specified by the link
parameter.
返回值
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
范例
Example #1 面向对象风格
<?php
$maxdb = new maxdb("localhost", "MONA", "RED", "DEMODB");
/* check connection */
if (maxdb_connect_errno()) {
printf("Connect failed: %s\n", maxdb_connect_error());
exit();
}
/* disable autocommit */
$maxdb->autocommit(FALSE);
$maxdb->query("CREATE TABLE temp.mycity LIKE hotel.city");
$maxdb->query("INSERT INTO temp.mycity SELECT * FROM hotel.city");
/* commit insert */
$maxdb->commit();
/* delete all rows */
$maxdb->query("DELETE FROM temp.mycity");
if ($result = $maxdb->query("SELECT COUNT(*) FROM temp.mycity")) {
$row = $result->fetch_row();
printf("%d rows in table mycity.\n", $row[0]);
/* Free result */
$result->close();
}
/* Rollback */
$maxdb->rollback();
if ($result = $maxdb->query("SELECT COUNT(*) FROM temp.mycity")) {
$row = $result->fetch_row();
printf("%d rows in table mycity (after rollback).\n", $row[0]);
/* Free result */
$result->close();
}
/* Drop table myCity */
$maxdb->query("DROP TABLE temp.mycity");
$maxdb->close();
?>
Example #2 过程化风格
<?php
$link = maxdb_connect("localhost", "MONA", "RED", "DEMODB");
/* check connection */
if (maxdb_connect_errno()) {
printf("Connect failed: %s\n", maxdb_connect_error());
exit();
}
/* disable autocommit */
maxdb_autocommit($link, FALSE);
maxdb_query($link, "CREATE TABLE temp.mycity LIKE hotel.city");
maxdb_query($link, "INSERT INTO temp.mycity SELECT * FROM hotel.city");
/* commit insert */
maxdb_commit($link);
/* delete all rows */
maxdb_query($link, "DELETE FROM temp.mycity");
if ($result = maxdb_query($link, "SELECT COUNT(*) FROM temp.mycity")) {
$row = maxdb_fetch_row($result);
printf("%d rows in table mycity.\n", $row[0]);
/* Free result */
maxdb_free_result($result);
}
/* Rollback */
maxdb_rollback($link);
if ($result = maxdb_query($link, "SELECT COUNT(*) FROM temp.mycity")) {
$row = maxdb_fetch_row($result);
printf("%d rows in table mycity (after rollback).\n", $row[0]);
/* Free result */
maxdb_free_result($result);
}
/* Drop table myCity */
maxdb_query($link, "DROP TABLE temp.mycity");
maxdb_close($link);
?>
以上例程的输出类似于:
0 rows in table mycity. 25 rows in table mycity (after rollback).
参见
- maxdb_commit() - Commits the current transaction
- maxdb_autocommit() - Turns on or off auto-commiting database modifications