如果执行存储过程没有取回行,则我想返回自定义值作为行的值。 Wǒ xiǎng huí tuì zìdìngyì zhí zuò wéi xíng de zhí shǔ jìn háng méi yǒu qǔhuò shí.
我该怎么办?
如果执行存储过程没有取回行,则我想返回自定义值作为行的值。 Wǒ xiǎng huí tuì zìdìngyì zhí zuò wéi xíng de zhí shǔ jìn háng méi yǒu qǔhuò shí.
我该怎么办?
你可以使用内置函数 ROW_COUNT()
来测试查询是否返回了任何行。如果返回的行数为零,则可以运行替代的 SQL 语句以返回自定义值:
--Execute your SQL statement
SELECT * FROM myTable
IF ROW_COUNT() = 0
BEGIN
--SQL to return your custom values instead
SELECT value1, value2, etc.
END
只需编写自己的SELECT语句,包含想要返回给用户的值。类似于这样:
Select
MyValue1,
MyValue2,
Myvalue3
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