Question

我在SQL Server中寻找一个查询，该查询将返回特定模式中所有表的给定年份的总行数，在本例中为dbo。

此架构中的所有表都有一个名为UPDT_TS的列，用于存储行更新的最后时间，并可用于此日期计算。

Answer 1

假设您有一个结果表来插入记录，您可以使用一个简单的游标：

DECLARE  @Iterator varchar(255)
        ,@strSQL varchar(MAX) 

DECLARE xyz CURSOR CURSOR FAST_FORWARD READ_ONLY
FOR
SELECT t.name
FROM  sys.schemas s
JOIN  sys.tables  t
  ON s.schema_id = t.schema_id
WHERE s.name = 'dbo'

OPEN xyz 
FETCH NEXT FROM xyz 
INTO @Iterator     
WHILE @@FETCH_STATUS = 0
BEGIN

SET @strSQL = 'INSERT INTO Results
           SELECT COUNT(*) as Rows, '''+@Iterator+''' as TableName
           FROM '+QUOTENAME(@Iterator)+'
           WHERE YEAR(UPDT_TS) = 2013          
           '
EXEC (@strSQL)

    FETCH NEXT FROM xyz 
    INTO @Iterator 
END   
CLOSE xyz 
DEALLOCATE xyz 
GO

每当处理动态sql时，将EXEC (@strSQL)更改为PRINT (@strSQL)可能会有所帮助，以确保您已将语法固定下来。

Answer 2

您可以使用简单的游标和动态SQL。

declare @v_Year int
set @v_Year = 2013

declare @v_TableName nvarchar(256)
declare @v_SQL nvarchar(max)
declare @v_Count int

declare @v_ResultTable table
(
    TableName nvarchar(256),
    [RowCount] int
)

declare cur cursor local fast_forward read_only for
select t.name from sys.tables as t
inner join sys.columns as c on t.object_id = c.object_id
where c.name = 'UPDT_TS' and t.schema_id = schema_id('dbo')

open cur

while (1=1)
begin

    fetch next from cur into @v_TableName

    if @@FETCH_STATUS <> 0
        break;

    set @v_SQL = 'select @v_Count = count(*) from '+QUOTENAME(@v_TableName)+' where year(UPDT_TS) = ' + cast(@v_Year as nvarchar(4))

    exec sp_executesql @v_SQL, N'@v_Count int output', @v_Count output

    insert into @v_ResultTable
    select @v_TableName, @v_Count

end

close cur
deallocate cur

select * from @v_ResultTable

修改在发布后看到Goat的回答:)看起来我们有同样的想法：）

Answer 3

这也可以：

DECLARE @sql NVARCHAR(max)
,@year INT

SET @year = 2013

SELECT @sql = 'select sum (total) from (' + SUBSTRING(cast((
            SELECT ' union select count(*) as Total 
                from ' + quotename(table_name) + ' 
                where 
                    UPDT_TS between dateadd(year,@year-1900,0) and dateadd(s,-1,dateadd(year,@year-1900+1,0))'
            FROM information_schema.columns
            WHERE column_name = 'UPDT_TS'
                AND TABLE_SCHEMA = 'dbo'
            FOR XML path('')
            ) AS NVARCHAR(max)), 8, 8000) + ') as Presum'

PRINT @sql

EXEC sp_executesql @sql
,N'@year int'
,@year = @year

在dbo架构中按年份的所有表的Rowcount

3 个答案: