我想使用动态SQL执行此查询,但是它不会影响@Exists
变量。问题是什么?
目的:检查数据库@TransformProcName
中是否存在名称为@TargetDb
的存储过程:
SET @Sql = N'IF NOT EXISTS (SELECT *
FROM ' + QUOTENAME(@TargetServer) + '.' + QUOTENAME(@TargetDB) + '
WHERE type = ''P'' AND OBJECT_ID = OBJECT_ID(N'''+QUOTENAME(@TargetSchema)+'.'+QUOTENAME(@TransformProcName)+'''))
SET @Exists = 0
ELSE
SET Exists = 1'
EXEC sp_executesql @Sql,N'@Exists bit OUTPUT', @Exists OUTPUT
答案 0 :(得分:4)
您在这里有几个问题。首先,您有SET Exists = 1
,应该为SET @Exists = 1
,但是您还引用了无效的对象。您需要在此处使用sys.procedures
和sys.schemas
,并且您不能使用OBJECT_ID
,因为它将在您连接的数据库的上下文中运行。这为您提供了以下内容(还整理了动态SQL):
DECLARE @SQL nvarchar(MAX);
DECLARE @TargetServer sysname, @TargetDB sysname, @TargetSchema sysname, @TransformProcName sysname;
SET @TargetDB = N'Sandbox';
SET @TargetSchema = N'dbo';
SET @TransformProcName = N'sample_sp';
DECLARE @Exists bit;
SET @Sql = N'IF NOT EXISTS (SELECT *' + NCHAR(13) + NCHAR(10) +
N' FROM ' + QUOTENAME(@TargetServer) + N'.' + QUOTENAME(@TargetDB) + '.sys.procedures p' + NCHAR(13) + NCHAR(10) +
N' JOIN sys.schemas s ON p.schema_id = s.schema_id' + NCHAR(13) + NCHAR(10) +
N' WHERE p.[name] = @TransformProcName' + NCHAR(13) + NCHAR(10) +
N' AND s.[name] = @TargetSchema)' + NCHAR(13) + NCHAR(10) +
N' SET @Exists = 0' + NCHAR(13) + NCHAR(10) +
N'ELSE' + NCHAR(13) + NCHAR(10) +
N' SET @Exists = 1;'
PRINT @SQl;
EXEC sp_executesql @Sql,N'@TransformProcName sysname, @TargetSchema sysname, @Exists bit OUTPUT', @TransformProcName = @TransformProcName, @TargetSchema = @TargetSchema, @Exists = @Exists OUTPUT;
PRINT @Exists;