将大量表移动到不同的文件组

Question

现有数据库在 PRIMARY 文件组中存储了大量表。我想根据表名的“前缀”自动将这些表及其索引移动到不同的文件组上。

例如，有 5 个表命名如下：

ABC_XXXX
ABC_YYYY
DEF_ZZZZ
DEF_TTTT
GHI_UUUU

ABC应将开头的所有表移到文件组FG1、DEF文件组FG2和其他表到文件组DEFAULT。

这可以使用以下命令完成CREATE INDEX：

CREATE (UNIQUE|CLUSTERED|) INDEX <Index Name> ON <Table Name>(<Index Columns>)
       WITH (DROP_EXISTING = ON) ON <New Filegroup>

这个命令最大的问题是按正确的顺序检索每个索引的列。

Answer 1

您在描述中遗漏了很多内容，脚本需要适应这些内容 - 索引是主键还是唯一约束？是否有任何列降序？索引被过滤了吗？它有任何 INCLUDE 列吗？虽然您当然可以手动生成脚本，但为什么不使用生成脚本向导呢？

1. 在对象资源管理器中，右键单击您的数据库
2. 选择任务 > 生成脚本...
3. 点击下一步
4. 选择“选择特定的数据库对象”，然后选择所有名为 ABC...
5. 点击下一步
6. 单击高级
7. 向下滚动并将“脚本索引”更改为 True
8. 单击确定
9. 将选项更改为“保存到新查询窗口”
10. 单击下一步/下一步/完成

现在您有一个包含所有脚本的查询窗口，您必须删除一些并对其他脚本进行一些手动按摩，但是对于不属于 PK 的索引，您应该只需能够搜索和替换DROP_EXISTING = OFF对DROP_EXISTING = ON，然后换出[PRIMARY]的FG1...

这是一个使用sys.indexes,sys.columns和sys.index_columns-的脚本，它在存在显式主键的情况下创建唯一索引（因为您没有提供DROP_EXISTING我要求的“使用”语法重新创建 PK ）。这涉及包含列、填充因子、将列按正确顺序排列，甚至确保首先构建唯一/聚集索引。

SET NOCOUNT ON;

DECLARE @sql NVARCHAR(MAX);

SET @sql = N'';

;WITH src AS
(
  SELECT 
    obj = QUOTENAME(OBJECT_SCHEMA_NAME(i.[object_id]))
    + '.' + QUOTENAME(OBJECT_NAME(i.[object_id])),
    i.[object_id],
    i.index_id,
    i.name,
    uniq = CASE i.is_unique WHEN 1 THEN ' UNIQUE' ELSE '' END,
    type_desc = i.type_desc COLLATE SQL_Latin1_General_CP1_CI_AS,
    ff = ', FILLFACTOR = ' + CONVERT(VARCHAR(3), i.fill_factor),
    dest = CASE LEFT(OBJECT_NAME(i.[object_id]), 3)
        WHEN 'ABC' THEN 'FG1'
        WHEN 'DEF' THEN 'FG2'
        ELSE 'DEFAULT'
        END
  FROM sys.indexes AS i
  INNER JOIN sys.partitions AS p
  ON i.[object_id] = p.[object_id]
  AND i.index_id = p.index_id
  WHERE i.index_id > 0
  -- AND OBJECT_NAME(i.object_id) IN ('list','of','tables')
),
cols AS
(
  SELECT
    name = QUOTENAME(c.name),
    ic.key_ordinal,
    ic.[object_id],
    ic.index_id,
    sort = CASE ic.is_descending_key WHEN 1 THEN ' DESC' ELSE ' ' END,
    ic.is_included_column
  FROM sys.index_columns AS ic
  INNER JOIN sys.columns AS c
  ON ic.[object_id] = c.[object_id]
  AND ic.column_id = c.column_id
  WHERE ic.[object_id] IN (SELECT [object_id] FROM src)
)
SELECT @sql = @sql + CHAR(13) + CHAR(10) 
    + N'CREATE ' + uniq + ' ' + type_desc + ' INDEX ' + QUOTENAME(name)
    + ' ON ' + obj + '(' + STUFF((SELECT ',' + name + sort FROM cols 
        WHERE cols.object_id = src.object_id 
        AND cols.index_id = src.index_id
        AND cols.is_included_column = 0
        ORDER BY cols.key_ordinal 
        FOR XML PATH('')), 1, 1, '') + ')' 
    + COALESCE(' INCLUDE(' + STUFF((SELECT ',' + name FROM cols 
        WHERE cols.[object_id] = src.[object_id] 
        AND cols.index_id = src.index_id
        AND cols.is_included_column = 1
        ORDER BY cols.key_ordinal 
        FOR XML PATH('')), 1, 1, '') + ')', '') 
    + ' WITH (DROP_EXISTING = ON' + ff
    + ') ON ' + dest + ';'
  FROM src
  ORDER BY uniq DESC, type_desc;

SELECT @sql;
-- EXEC sp_executesql @sql;

为了完整起见，这里有一个脚本，它添加了sys.partitions几个 SQL Server 2008 特定的功能，例如筛选索引和数据压缩。

SET NOCOUNT ON;

DECLARE @sql NVARCHAR(MAX);

SET @sql = N'';

;WITH src AS
(
  SELECT 
    obj = QUOTENAME(OBJECT_SCHEMA_NAME(i.[object_id]))
    + '.' + QUOTENAME(OBJECT_NAME(i.[object_id])),
    i.[object_id],
    i.index_id,
    i.name,
    uniq = CASE i.is_unique WHEN 1 THEN ' UNIQUE' ELSE '' END,
    type_desc = i.type_desc COLLATE SQL_Latin1_General_CP1_CI_AS,
    filter = CASE WHEN i.has_filter = 1 THEN ' WHERE ' + i.filter_definition ELSE '' END,
    ff = ', FILLFACTOR = ' + CONVERT(VARCHAR(3), i.fill_factor),
    dc = CASE p.data_compression_desc WHEN 'NONE' THEN '' 
        ELSE ', DATA_COMPRESSION = ' + p.data_compression_desc END,
    dest = CASE LEFT(OBJECT_NAME(i.[object_id]), 3)
        WHEN 'ABC' THEN 'FG1'
        WHEN 'DEF' THEN 'FG2'
        ELSE 'DEFAULT'
        END
  FROM sys.indexes AS i
  INNER JOIN sys.partitions AS p
  ON i.[object_id] = p.[object_id]
  AND i.index_id = p.index_id
  WHERE i.index_id > 0
  -- AND OBJECT_NAME(i.object_id) IN ('list','of','tables')
),
cols AS
(
  SELECT
    name = QUOTENAME(c.name),
    ic.key_ordinal,
    ic.[object_id],
    ic.index_id,
    sort = CASE ic.is_descending_key WHEN 1 THEN ' DESC' ELSE ' ' END,
    ic.is_included_column
  FROM sys.index_columns AS ic
  INNER JOIN sys.columns AS c
  ON ic.[object_id] = c.[object_id]
  AND ic.column_id = c.column_id
  WHERE ic.[object_id] IN (SELECT [object_id] FROM src)
)
SELECT @sql = @sql + CHAR(13) + CHAR(10) 
    + N'CREATE ' + uniq + ' ' + type_desc + ' INDEX ' + QUOTENAME(name)
    + ' ON ' + obj + '(' + STUFF((SELECT ',' + name + sort FROM cols 
        WHERE cols.object_id = src.object_id 
        AND cols.index_id = src.index_id
        AND cols.is_included_column = 0
        ORDER BY cols.key_ordinal 
        FOR XML PATH('')), 1, 1, '') + ')' 
    + COALESCE(' INCLUDE(' + STUFF((SELECT ',' + name FROM cols 
        WHERE cols.[object_id] = src.[object_id] 
        AND cols.index_id = src.index_id
        AND cols.is_included_column = 1
        ORDER BY cols.key_ordinal 
        FOR XML PATH('')), 1, 1, '') + ')', '') 
    + filter + ' WITH (DROP_EXISTING = ON' + ff + dc
    + ') ON ' + dest + ';'
  FROM src
  ORDER BY uniq DESC, type_desc;

SELECT @sql;
-- EXEC sp_executesql @sql;