如果不存在,我需要添加一个特定的列.我有类似以下内容,但它总是返回false:
IF EXISTS(SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'myTableName'
AND COLUMN_NAME = 'myColumnName')
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如何检查SQL Server数据库的表中是否存在列?
t-sql sql-server sql-server-2008 sql-server-2012 sql-server-2016
我试过这个:
ALTER TABLE My.Table DROP MyField
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并得到此错误:
-MyField不是约束.
- 不要放弃约束.查看以前的错误.
表中只有一行数据,只是添加了字段.
编辑: 只是为了跟进,sql确实缺少了COLUMN.现在我更加认真地看错了:
编辑:
ALTER TABLE TableName DROP Constraint ConstraintName
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工作,之后,我能够使用以前的代码删除列.感谢你们两个,谢谢.
一个*.ini
文件具有恒定:APPLICATION_PATH
APPLICATION_PATH何时设置,它是如何工作的?
; application/configs/application.ini
[production]
; PHP settings we want to initialize
phpSettings.display_startup_errors = 0
phpSettings.display_errors = 0
includePaths.library = APPLICATION_PATH "/../library"
bootstrap.path = APPLICATION_PATH "/Bootstrap.php"
bootstrap.class = "Bootstrap"
appnamespace = "Application"
resources.frontController.controllerDirectory = APPLICATION_PATH "/controllers"
resources.frontController.params.displayExceptions = 0
resources.layout.layoutPath = APPLICATION_PATH "/layouts/scripts"
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