TSQL语法错误：缺少'if'(TSQL Syntax error: missing 'if')

TSQL语法错误：缺少'if'(TSQL Syntax error: missing 'if')

我正在制作一个学校项目的程序，如果它没有被使用，它会从课程表中删除一个特定的课程。

根据我读过的所有内容，这是正确的设置，但是在最后一个“结束”中是错误的。 表示如果有“缺失”的话

Delimiter // CREATE PROCEDURE DeleteCourse ( pCourseNumber varchar (7) ) BEGIN if NOT EXISTS(SELECT * FROM trackcourses WHERE courseNumber = pCourseNumber) then BEGIN DELETE FROM courses WHERE courseNumber = pCourseNumber; DELETE FROM restrictors WHERE courseNumber = pCourseNumber; select row_count(); END; else BEGIN return 'Course could not be deleted'; END; END; // <-- Syntax error: missing 'if'

任何想法和想法都非常感谢！

谢谢，

奇怪的。

I'm making a procedure for a school project that removes a specific course from the course table if it's not in use.

According to everything I've read this is the correct setup but tere's an error on that last "END;" line that says there's a "missing 'if'"

Delimiter // CREATE PROCEDURE DeleteCourse ( pCourseNumber varchar (7) ) BEGIN if NOT EXISTS(SELECT * FROM trackcourses WHERE courseNumber = pCourseNumber) then BEGIN DELETE FROM courses WHERE courseNumber = pCourseNumber; DELETE FROM restrictors WHERE courseNumber = pCourseNumber; select row_count(); END; else BEGIN return 'Course could not be deleted'; END; END; // <-- Syntax error: missing 'if'

Any thoughts and ideas are greatly appreciated!

Thanks,

Weird.

最满意答案

您可能需要在与IF相同的行上使用THEN ，并使用END IF而不是BEGIN END块。

IF <statement> THEN ... END IF

请参阅这里了解MySQL语法

如果你只是使用：

... IF NOT EXISTS(SELECT * FROM trackcourses WHERE courseNumber = pCourseNumber) THEN DELETE FROM courses WHERE courseNumber = pCourseNumber; DELETE FROM restrictors WHERE courseNumber = pCourseNumber; select row_count(); ELSE RETURN 'Course could not be deleted'; END IF ...

应该没问题

You may need to use the word THEN on the same line as the IF, and use END IF instead of BEGIN END blocks.

IF <statement> THEN ... END IF

See here for MySQL syntax

If you just use:

... IF NOT EXISTS(SELECT * FROM trackcourses WHERE courseNumber = pCourseNumber) THEN DELETE FROM courses WHERE courseNumber = pCourseNumber; DELETE FROM restrictors WHERE courseNumber = pCourseNumber; select row_count(); ELSE RETURN 'Course could not be deleted'; END IF ...

It should be fine