| Server IP : 104.21.38.3 / Your IP : 162.158.88.163 Web Server : Apache System : Linux krdc-ubuntu-s-2vcpu-4gb-amd-blr1-01.localdomain 5.15.0-142-generic #152-Ubuntu SMP Mon May 19 10:54:31 UTC 2025 x86_64 User : www ( 1000) PHP Version : 7.4.33 Disable Function : passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : OFF | Sudo : ON | Pkexec : ON Directory : /www/server/mysql/src/mysql-test/suite/innodb/r/ |
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# # TRUNCATE TABLE # # Truncating is disallowed for parent tables unless such table # participates in self-referencing foreign keys only. # CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=INNODB; CREATE TABLE t2 (fk INT NOT NULL, FOREIGN KEY (fk) REFERENCES t1 (pk)) ENGINE=INNODB; TRUNCATE TABLE t1; ERROR 42000: Cannot truncate a table referenced in a foreign key constraint (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`fk`) REFERENCES `test`.`t1` (`pk`)) # Truncation of child should succeed. TRUNCATE TABLE t2; DROP TABLE t2; DROP TABLE t1; CREATE TABLE t1 (pk INT PRIMARY KEY, fk INT, FOREIGN KEY (fk) REFERENCES t1 (pk)) ENGINE=INNODB; # Truncation of self-referencing table should succeed. TRUNCATE TABLE t1; DROP TABLE t1; # # Also, truncating such tables is allowed if foreign key # checks are disabled. # SET @old_foreign_key_checks = @@SESSION.foreign_key_checks; CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=INNODB; CREATE TABLE t2 (fk INT NOT NULL, FOREIGN KEY (fk) REFERENCES t1 (pk)) ENGINE=INNODB; CREATE TABLE t3 (pk INT PRIMARY KEY, fk INT, FOREIGN KEY (fk) REFERENCES t1 (pk)) ENGINE=INNODB; SET @@SESSION.foreign_key_checks = 0; TRUNCATE TABLE t1; TRUNCATE TABLE t2; TRUNCATE TABLE t3; SET @@SESSION.foreign_key_checks = 1; TRUNCATE TABLE t1; ERROR 42000: Cannot truncate a table referenced in a foreign key constraint (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`fk`) REFERENCES `test`.`t1` (`pk`)) TRUNCATE TABLE t2; TRUNCATE TABLE t3; LOCK TABLES t1 WRITE; SET @@SESSION.foreign_key_checks = 0; TRUNCATE TABLE t1; SET @@SESSION.foreign_key_checks = 1; TRUNCATE TABLE t1; ERROR 42000: Cannot truncate a table referenced in a foreign key constraint (`test`.`t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`fk`) REFERENCES `test`.`t1` (`pk`)) UNLOCK TABLES; DROP TABLE t3,t2,t1; SET @@SESSION.foreign_key_checks = @old_foreign_key_checks; # # Test that TRUNCATE resets auto-increment. # CREATE TABLE t1 (a INT PRIMARY KEY NOT NULL AUTO_INCREMENT); INSERT INTO t1 VALUES (NULL), (NULL); SELECT AUTO_INCREMENT FROM INFORMATION_SCHEMA.TABLES WHERE table_name = 't1'; AUTO_INCREMENT 3 SELECT * FROM t1 ORDER BY a; a 1 2 TRUNCATE TABLE t1; SELECT AUTO_INCREMENT FROM INFORMATION_SCHEMA.TABLES WHERE table_name = 't1'; AUTO_INCREMENT 1 INSERT INTO t1 VALUES (NULL), (NULL); SELECT * FROM t1 ORDER BY a; a 1 2 DROP TABLE t1;