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  • 数据库重组或者重建索引

    /*功能描述:自动重新组织或重新生成数据库中平均碎片超过 10% 的所有分区。
    执行此查询需注意以下几点:
    1)、需要 VIEW DATABASE STATE 权限。
    2)、在不指定数据库名称的情况下,指定 DB_ID 作为第一个参数。
    3)、确定当前数据库为80以上。
    */
    USE MASTER
    SET NOCOUNT ON;
    DECLARE @objectid int;
    DECLARE @indexid int;
    DECLARE @partitioncount bigint;
    DECLARE @schemaname nvarchar(130); 
    DECLARE @objectname nvarchar(130); 
    DECLARE @indexname nvarchar(130); 
    DECLARE @partitionnum bigint;
    DECLARE @partitions bigint;
    DECLARE @frag float;
    DECLARE @command nvarchar(4000); 
    SELECT
        object_id AS objectid,
        index_id AS indexid,
        partition_number AS partitionnum,
        avg_fragmentation_in_percent AS frag
    INTO #work_to_do
    FROM sys.dm_db_index_physical_stats (db_id(), NULL, NULL , NULL, 'LIMITED')
    WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;
    DECLARE partitions CURSOR FOR SELECT * FROM #work_to_do;
    OPEN partitions;
    WHILE (1=1)
        BEGIN;
            FETCH NEXT
               FROM partitions
               INTO @objectid, @indexid, @partitionnum, @frag;
            IF @@FETCH_STATUS < 0 BREAK;
            SELECT @objectname = QUOTENAME(o.name), @schemaname = QUOTENAME(s.name)
            FROM sys.objects AS o
            JOIN sys.schemas as s ON s.schema_id = o.schema_id
            WHERE o.object_id = @objectid;
            SELECT @indexname = QUOTENAME(name)
            FROM sys.indexes
            WHERE  object_id = @objectid AND index_id = @indexid;
            SELECT @partitioncount = count (*)
            FROM sys.partitions
            WHERE object_id = @objectid AND index_id = @indexid;
    
            IF @frag < 30.0
                SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REORGANIZE';
            IF @frag >= 30.0
                SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REBUILD';
            IF @partitioncount > 1
                SET @command = @command + N' PARTITION=' + CAST(@partitionnum AS nvarchar(10));
            EXEC (@command);
            PRINT N'Executed: ' + @command;
        END;
    CLOSE partitions;
    DEALLOCATE partitions;
    DROP TABLE #work_to_do;
    GO
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  • 原文地址:https://www.cnblogs.com/maomao999/p/4522157.html
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