SQL> create table tbl_a(id number, remark varchar2(1)); Table created. SQL> create table tbl_b(id number, a_id number, remark varchar2(1)); Table created. SQL> alter table tbl_a add constraint pk_tbl_a primary key(id); Table altered. SQL> alter table tbl_b add constraint pk_...
使用mysql ,常常是基于图像界面的客户端操作,Command Line Client下,用到的两个不错的sql命令,如下。 1. truncate table XXX 在测试时,我很讨厌某表的主键一直自增长下去,总觉得从1开始最舒服,^_^,truncate table 就可以帮我,相比delete from 来说,它使数据表中自增长的字段起始值归为1; 2.source 命令 用...
To delete all the rows from the employee table, the query would be like, DELETE FROM employee; SQL TRUNCATE StatementThe SQL TRUNCATE command is used to delete all the rows from the table and free the space containing the table.Syntax to TRUNCATE a table:TRUNCATE TABLE table_name; ...
If the table is cached, the command clears cached data of the table and all its dependents that refer to it. The cache will be lazily filled when the table or the dependents are accessed the next time.SyntaxTRUNCATE TABLE table_name [ PARTITION clause ] ...
TRUNCATE是 MySQL 中的一个 SQL 命令,用于快速删除表中的所有数据,但不删除表本身。这个命令比DELETE更快,因为它不会记录单个行的删除操作,也不会触发任何删除触发器。 基础概念 TRUNCATE TABLE: 这个命令会移除表中的所有行,但保留表的结构、列、约束和索引。
Truncate table _name; truncate table table_name; Redshift's syntax for describing parameters related to truncation. The truncate command in Redshift enables the deletion of all the entries in a table, thus allowing for the removal of all the records from the table . ...
Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.
Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.
Table created SQL> alter table t add constraint pk_t_id primary key (id); Table altered //建立字表m SQL> create table m (cid number, tid number, cname varchar2(100)); Table created SQL> alter table m add constraint pk_m_cid primary key (cid); ...
this table or a NONRECOVERABLE load on this table.猜测用truncate清空表后,恢复数据库时,不会导致数据库前滚。以下是实验步骤:[db2inst1@localhost tmp]$ db2 drop table liyj.test1DB20000I The SQL command completed successfully.[db2inst1@localhost tmp]$ db2 "create table liyj.test1(col1 int)"DB...