Only the owner of a table may TRUNCATE it. TRUNCATE cannot be used on a table that has foreign-key references from other tables, unless all such tables are also truncated in the same command. Checking validity in such cases would require table scans, and the whole point is not to do one...
including the table's structure. While the DELETE and TRUNCATE commands remove entries/records from the given table and retain the table structure. The TRUNCATE command always removes all the data of the selected table, while the DELETE command can delete the entire table or some specific table ...
Truncate operations drop and re-create the table, which is much faster than deleting rows one by one, particularly for large tables. 文档给出的解释是尽管truncate和delete的功能很像,但是truncate被归类为DDL语言,而delete则是DML语言。相对于delete一行行删除数据,truncate会删除表后重新新建表,这一操作相对...
TRUNCATEcannot be used on a table that has foreign-key references from other tables, unless all such tables are also truncated in the same command. Checking validity in such cases would require table scans, and the whole point is not to do one. TRUNCATEwill not run any user-definedON DELET...
Difference between TRUNCATE and DELETE commands Submitted by Dipal havsar (not verified) on Tue, 2006-09-19 07:39. 1>TRUNCATE is a DDL command whereas DELETE is a DML command. 2>TRUNCATE is much faster than DELETE. Reason:When you type DELETE.all the data get copied into the Rollback...
对DROP和TRUNCATE慎之又慎 不管在什么环境,要删除表时,永远不要直接删。而是要保证 总是把要删的表的表名改了 运行一段时间后,程序没有问题,再真的删 代码语言:javascript 复制 ALTERTABLEtbl_nameRENAMETOtal_name_tobedel 删除数据库时,因为MySQL不支持改数据库的名字,所以要修改所有这个数据库里的表名。但是...
Unlike thedeletecommand, it doesn't scan over the entire table. We also have the ability totruncatemore than one table with just one statement by listing the other tables with commas. Finally, if we're trying to remove the table completely from our database, we use thedropcommand. ...
Truncate a Table 截表 What if we only want to get rid of the data inside a table, and not the table itself? Use the TRUNCATE TABLE command (deletes only the data inside the table): 当我们只想将表内的数据做完成清楚而保留其内部结构的话,可以使用TRUNCATE TABLE命令(仅仅删除表中的数据) ...
Recovery Manager complete. 3.3.3 HR 用户下建一张表T1 模拟问题 先插入27 条数据,后删除7 条数据,最后truncate 这张表,要求把数据恢复到20 条数据的状态。 SQL>connect hr/hr Connected. SQL>showuserUSERis"HR" SQL>createtableT1 tablespace users2...
truncate scott.test_tab_1 * ERROR at line 1: ORA-03290: Invalid truncate command - missing CLUSTER or TABLE keyword SQL> truncate table scott.test_tab_1 ; Table truncated. SQL> 备库: SQL> show parameter target NAME TYPE VALUE --- --- --- archive_lag_target integer 0 db_flashback_...