There are two ways to accomplish this task. The first is by utilizing a SQL procedure or script. The second method involves using plain SQL statements with theIFcondition to check for the existence of the table before truncating it. Alternatively, you can use theCreatetable in conjunction with...
(rowcount=>20)) v; -- verify that the rows exist SELECT COUNT (*) FROM temp; ---+ count(*) | ---+ 20 | ---+ -- truncate the table TRUNCATE TABLE IF EXISTS temp; -- verify that the table is now empty SELECT COUNT (*) FROM temp; ---+ count(*) | ---+ 0 | ---+...
TRUNCATE TABLE TRUNCATETABLE[IFEXISTS][db.]name[ONCLUSTER cluster] Removes all data from a table. When the clauseIF EXISTSis omitted, the query returns an error if the table does not exist. TheTRUNCATEquery is not supported forView,File,URL,BufferandNulltable engines. ...
the table exists. If the table does exist, it is truncated; if it does not exist, the statement has no effect. This capability is useful in standardized setup scripts that are might be run both before and after some of the tables exist. This clause is available in Impala 2.5 and higher...
TRUNCATE TABLE TRUNCATE TABLE [IF EXISTS] [db.]name [ON CLUSTER cluster] Removes all data from a table. When the clause IF EXISTS is omitted, the query returns an error if the table does not exist. The TRUNCATE query is not supported for View, File, URL, Buffer and Null table engines...
华为云帮助中心为你分享云计算行业信息,包含产品介绍、用户指南、开发指南、最佳实践和常见问题等文档,方便快速查找定位问题与能力成长,并提供相关资料和解决方案。本页面关键词:华为table。
华为云帮助中心为你分享云计算行业信息,包含产品介绍、用户指南、开发指南、最佳实践和常见问题等文档,方便快速查找定位问题与能力成长,并提供相关资料和解决方案。本页面关键词:创建table。
SqlConnection sqlconn = new SqlConnection(ConStr);SqlCommand sqlcmd = sqlconn.CreateCommand();sqlconn.Open();string tableName = "test";string sqlstr = "truncate table tablename";sqlcmd.CommandText = sqlstr;object isExist = sqlcmd.ExecuteScalar();if (isExist.ToString() != "1"...
在数据库管理中,DROP TABLE和TRUNCATE TABLE是两种常用的操作,它们之间有一些区别。 TRUNCATE TABLE TRUNCATE TABLE用于删除表中的所有数据,但不删除表本身。它的主要特点如下: 速度快:由于不记录每一行的删除操作,TRUNCATE TABLE通常比DELETE操作更快。 自动重置:TRUNCATE TABLE会重置主键和自增列的值。
设置 innodb_flush_method = fsync (root@127.1) [eolbimsdb] 09:03:34 28> truncate table ...