在SQL Server 2008数据库的所有表中查找公共列的最小和最大列值

Question

我正在检查第三方SQL Server 2008数据库。在这个数据库中，有2列CREATED_DATETIME和UPDATED_DATETIME，它们存在于大多数表格中，但可能不是全部。

我想找到这两列的最小值和最大值跨数据库中所有表中的这2列。这会给我一个公平的想法，即数据库中的数据是从哪个阶段到哪个阶段。

我该如何编写这样的查询？

Answer 1

运行下面链接中提到的脚本。您必须根据您的要求稍作修改。

SCRIPT to Search every Table and Field

Answer 2

select MIN(CREATED_DATETIME) MinCREATED_DATETIME_Table1, MAX(CREATED_DATETIME) MaxCREATED_DATETIME_Table1, MIN(CREATED_DATETIME) MinCREATED_DATETIME_Table2, MAX(CREATED_DATETIME) MaxCREATED_DATETIME_Table2 from Table1, Table2 

Answer 3

像下面的东西应该工作

DECLARE @C1   AS CURSOR, 
     @TABLE_SCHEMA SYSNAME, 
     @TABLE_NAME SYSNAME, 
     @HasCreated BIT, 
     @HasUpdated BIT, 
     @MaxDate  DATETIME, 
     @MinDate  DATETIME, 
     @SQL   NVARCHAR(MAX) 

SET @C1 = CURSOR FAST_FORWARD FOR 
SELECT TABLE_SCHEMA, 
     TABLE_NAME, 
     COUNT(CASE 
       WHEN COLUMN_NAME = 'CREATED_DATETIME' THEN 1 
      END) AS HasCreated, 
     COUNT(CASE 
       WHEN COLUMN_NAME = 'UPDATED_DATETIME' THEN 1 
      END) AS HasUpdated 
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE COLUMN_NAME IN ('CREATED_DATETIME', 'UPDATED_DATETIME') 
GROUP BY TABLE_SCHEMA, 
      TABLE_NAME 


OPEN @C1; 

FETCH NEXT FROM @C1 INTO @TABLE_SCHEMA , @TABLE_NAME , @HasCreated , @HasUpdated ; 
WHILE @@FETCH_STATUS = 0 
BEGIN 

SET @SQL = N' 
SELECT @MaxDate = MAX(D), 
     @MinDate = MIN(D) 
FROM ' + QUOTENAME(@TABLE_SCHEMA) + '.' + QUOTENAME(@TABLE_NAME) + N' 
     CROSS APPLY (VALUES ' + 
        CASE WHEN @HasCreated = 1 THEN N'(CREATED_DATETIME),' ELSE '' END + 
        CASE WHEN @HasUpdated = 1 THEN N'(UPDATED_DATETIME),' ELSE '' END + N' 
          (@MaxDate), 
          (@MinDate)) V(D) 

' 

EXEC sp_executesql 
    @SQL, 
    N'@MaxDate datetime OUTPUT, @MinDate datetime OUTPUT', 
    @MaxDate = @MaxDate OUTPUT, 
    @MinDate = @MinDate OUTPUT 

    FETCH NEXT FROM @C1 INTO @TABLE_SCHEMA , @TABLE_NAME , @HasCreated , @HasUpdated ; 
END 

SELECT @MaxDate AS [@MaxDate], @MinDate AS [@MinDate] 

Answer 4

运行此脚本在SSMS（CTrl+T =文字结果，F5 =执行查询）：

SET NOCOUNT ON; 

SELECT 'SELECT MIN(' 
     + QUOTENAME(c.COLUMN_NAME) 
     + ') AS ' 
     + QUOTENAME('Min '+c.TABLE_NAME+'.'+c.COLUMN_NAME) 
     + ', MAX(' 
     + QUOTENAME(c.COLUMN_NAME) 
     + ') AS ' 
     + QUOTENAME('Max_'+c.TABLE_NAME+'.'+c.COLUMN_NAME)  
     + CHAR(13) 
     + 'FROM ' + QUOTENAME(c.TABLE_SCHEMA)+'.'+QUOTENAME(c.TABLE_NAME) 
FROM INFORMATION_SCHEMA.COLUMNS c 
WHERE c.COLUMN_NAME IN ('CREATED_DATETIME', 'UPDATED_DATETIME') 
ORDER BY c.TABLE_SCHEMA, c.TABLE_NAME, c.COLUMN_NAME; 

SET NOCOUNT OFF; 

它会生成另一个脚本。执行生成的脚本。

例（为master数据库生成的脚本，并与low列名>WHERE c.COLUMN_NAME IN (N'low')所有表）：

SELECT MIN([low]) AS [Min spt_fallback_dev.low], MAX([low]) AS [Max_spt_fallback_dev.low] 
FROM [dbo].[spt_fallback_dev] 
SELECT MIN([low]) AS [Min spt_values.low], MAX([low]) AS [Max_spt_values.low] 
FROM [dbo].[spt_values]