truncate table table_name; 1. 2.说明 (1)默认情况下,truncate通过释放存储表数据所用的数据页来删除数据,并且只在事务日志中记录页的释放。所以使用的系统和事务日志资源少,可以使用reuse storage; truncate会将高水线复位(回到最开始). (2) truncate是DDL语言, 操作立即生效,自动提交,原数据不放到rollback segm...
使用时机:不再需要一张表的时候,用drop 14.5.2 truncate table 1)属于DDL 2)不可回滚 3)不可带where 4)表内容删除 5)删除速度快 使用时机:保留表而删除所有数据的时候用truncate 14.5.3 delete from 1)属于DML 2)可回滚 3)可带where 4)根据where对表内容删除 5)删除速度慢,需要逐行删除 使用时机:想删除...
SET FOREIGN_KEY_CHECKS=0 \g truncate Table user_name$your_database_name.table_name \g SET FOREIGN_KEY_CHECKS=1 \g 4.6.2. Tips [1] 数据库会返回一个迷惑人结果,如下: Query OK, 0 rows affected (0.03 sec) 但是实际上,SQL命令已经执行成功了。我也不知道为什么会返回这么奇怪的回复... [2]...
Oracle imposes a name length limit of 30 characters. To accommodate this, the backend truncates database identifiers to fit, replacing the final four characters of the truncated name with a repeatable MD5 hash value. Additionally, the backend turns database identifiers to all-uppercase. ...
A TestCase, on the other hand, does not truncate tables after a test. Instead, it encloses the test code in a database transaction that is rolled back at the end of the test. This guarantees that the rollback at the end of the test restores the database to its initial state. Warnin...
self.db_table =truncate_name(self.db_table, connection.ops.max_name_length()) File "G:\PythonLearning\django_project\venv\lib\site-packages\django\db\__init__.py", line 33, in __getattr__ returngetattr(connections[DEFAULT_DB_ALIAS], item) ...
ALTER TABLE shucaiyidate_vsixxieyiduizhao AUTO_INCREMENT=1 方法三: truncate tbname ; 直接清空所有数据,并将auto_increment重置为0。 例如: 表名:shucaiyidate_vsixxieyiduizhao truncate shucaiyidate_vsixxieyiduizhao 重置完成后,要重启数据库才能生效...
AI代码解释 第一类:RemovedInDjango20Warning: on_delete will be a required arg for ForeignKey in Django 2.0 第二类:RemovedInDjango20Warning: Old-style middleware using settings.MIDDLEWARE_CLASSES is deprecated. Update your middleware and use settings.MIDDLEWARE instead. ...
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())File "D:\SoftDevelopment\Anaconda3\envs\untitled4\lib\site-packages\django\db\__init__.py", line 28, in __getattr__return getattr(connections[DEFAULT_DB_ALIAS], item)File "D:\SoftDevelopment\Anaconda3\envs...
PostgreSQL 11.x declarative table partitioning Supports both range and list partitioning Faster deletes Truncate tables (with cascade) Indexes Conditional unique index. Case sensitive unique index. Getting started Clone the repository: Create a virtual environment: ...