pl/sql工具中,要更改某行某个字段的值: 法1. 反键该表--》编辑数据。 这种方法,对于数据量少的时候,可以一眼看出来你要更改的
pl/sql工具中,要更改某行某个字段的值:
法1.
反键该表--》编辑数据。
这种方法,对于数据量少的时候,可以一眼看出来你要更改的数据,很好更改。
但是数据量大了的时候,就要用到update语句。
如果update一个clob型的数据,例如下面的allcode字段是clob型的。
update..set allcode='.......'
这样写是错误的,因为clob是对象型的数据,不能用单引号引起来。再者,一般clob型的数据内容都比较多,你这样直接update要把新值全部写里面,,很麻烦,也不一定新值能写全。所以,正确的更改clob型数据值的方法是这样的:
1.将要更改的那一行,select for update。那么这一行数据select出来之后,会被锁住。这个锁在pl/sql编辑器显示数据的上方,是锁住的样子。
2.把锁点开,鼠标放在锁上,应该会显示“编辑数据”几个字。点开后,锁变成了开着的锁的样子。
3.直接找到你要更改的clob那个字段,点字段旁边的省略号,在里面更改,更改完后关闭窗口,提示你保存。保存之后,该提交的提交。这样就更改完成了。

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