sql - 从表列表动态创建sql表

Question

我正在尝试基于从另一个模式中提取其表名的表列表在模式中创建一堆表

例子

SCHA 表 1 SCHA 表 2 SCHA 表 3

dbo tablelist 在架构 schA 中包含此表

所以要么我需要一些代码说看看dbo tablelist验证它是否存在我如果不从数据库表中选择表结构到schB（这不存在）

我的问题是循环

我不是要求某人完全编写此代码（尽管会有所帮助:-)，但如何构建我的查询或最好的开始方式

超级感谢提前

Answer 1

可能这对你有帮助-

DDL：

CREATE TABLE [dbo].[test1](
    [company_id] [int] NOT NULL PRIMARY KEY,
    [staff_name] [nvarchar](50) NULL,
    [email] [nvarchar](50) NULL
) ON [PRIMARY]

询问：

DECLARE 
      @table_name SYSNAME
    , @name_for_new_table SYSNAME
    , @schema_for_new_table SYSNAME

SELECT 
      @table_name = 'dbo.test1'
    , @schema_for_new_table = 'dbo' 
    , @name_for_new_table = 'test1_new'

DECLARE @SQL NVARCHAR(MAX) = ''

;WITH tbl AS 
(
    SELECT o.[object_id]
    FROM sys.objects o WITH (NOWAIT)
    WHERE SCHEMA_NAME(o.[schema_id]) + '.' + o.name = @table_name
        AND o.[type] = 'U'
        AND o.is_ms_shipped = 0
),
index_column AS 
(
    SELECT 
          ic.[object_id]
        , ic.index_id
        , ic.is_descending_key
        , ic.is_included_column
        , c.name
    FROM sys.index_columns ic WITH (NOWAIT)
    JOIN sys.columns c WITH (NOWAIT) ON ic.[object_id] = c.[object_id] AND ic.column_id = c.column_id
    WHERE ic.[object_id] IN (SELECT t.[object_id] FROM tbl t)
),
fk_columns AS 
(
     SELECT 
          k.constraint_object_id
        , cname = c.name
        , rcname = rc.name
    FROM sys.foreign_key_columns k WITH (NOWAIT)
    JOIN sys.columns rc WITH (NOWAIT) ON rc.[object_id] = k.referenced_object_id AND rc.column_id = k.referenced_column_id 
    JOIN sys.columns c WITH (NOWAIT) ON c.[object_id] = k.parent_object_id AND c.column_id = k.parent_column_id
)
SELECT @SQL = 'CREATE TABLE [' + @schema_for_new_table + '].[' + @name_for_new_table + ']' + CHAR(13) + '(' + CHAR(13) + STUFF((
    SELECT DISTINCT CHAR(9) + ', [' + c.name + '] ' + UPPER(t.name) + 
        CASE WHEN t.name IN ('varchar', 'char', 'varbinary', 'binary', 'text')
               THEN '(' + CASE WHEN c.max_length = -1 THEN N'MAX' ELSE CAST(c.max_length AS NVARCHAR(5)) END + ')'
             WHEN t.name IN ('nvarchar', 'nchar', 'ntext')
               THEN '(' + CASE WHEN c.max_length = -1 THEN N'MAX' ELSE CAST(c.max_length / 2 AS NVARCHAR(5)) END + ')'
             WHEN t.name IN ('datetime2', 'time2', 'datetimeoffset') 
               THEN '(' + CAST(c.scale AS NVARCHAR(5)) + ')'
             WHEN t.name = 'decimal' 
               THEN '(' + CAST(c.[precision] AS NVARCHAR(5)) + ',' + CAST(c.scale AS NVARCHAR(5)) + ')'
            ELSE ''
        END +
        CASE WHEN c.collation_name IS NOT NULL THEN ' COLLATE ' + c.collation_name ELSE '' END +
        CASE WHEN c.is_nullable = 1 THEN ' NULL' ELSE ' NOT NULL' END +
        CASE WHEN c.[definition] IS NOT NULL THEN ' DEFAULT' + c.[definition] ELSE '' END + 
        CASE WHEN c.is_identity = 1 THEN ' IDENTITY(' + CAST(ISNULL(c.seed_value, '0') AS CHAR(1)) + ',' + CAST(ISNULL(c.increment_value, '1') AS CHAR(1)) + ')' ELSE '' END + CHAR(13)
    FROM (
        SELECT 
              c.name
            , c.user_type_id
            , c.max_length
            , c.[precision]
            , c.scale
            , dc.[definition]
            , ic.seed_value
            , ic.increment_value
            , c.collation_name
            , c.is_nullable
            , c.is_identity 
        FROM sys.columns c WITH (NOWAIT)
        LEFT JOIN sys.default_constraints dc WITH (NOWAIT) ON c.default_object_id != 0 AND c.[object_id] = dc.parent_object_id AND c.column_id = dc.parent_column_id
        LEFT JOIN sys.identity_columns ic WITH (NOWAIT) ON c.is_identity = 1 AND c.[object_id] = ic.[object_id] AND c.column_id = ic.column_id
        WHERE c.[object_id] IN (SELECT o.[object_id] FROM tbl o)
    ) c
    JOIN sys.types t WITH (NOWAIT) ON c.user_type_id = t.user_type_id
    FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, CHAR(9) + ' ')
    + ISNULL((SELECT CHAR(9) + ', CONSTRAINT [PK_' + @schema_for_new_table + '_' + @name_for_new_table + '] PRIMARY KEY (' + 
            (SELECT STUFF((
             SELECT DISTINCT ', [' + c.name + ']' + CASE WHEN ic.is_descending_key = 1 THEN ' DESC' ELSE ' ASC' END
             FROM sys.key_constraints k WITH (NOWAIT) 
             JOIN sys.index_columns ic WITH (NOWAIT) ON ic.[object_id] = k.parent_object_id AND ic.index_id = k.unique_index_id
             JOIN sys.columns c WITH (NOWAIT) ON c.[object_id] = k.parent_object_id AND c.column_id = ic.column_id
             WHERE k.[type] = 'PK'
                 AND ic.is_included_column = 0
                 AND k.parent_object_id IN (SELECT t.[object_id] FROM tbl t)
             FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, '')) + ')'  + CHAR(13)), '')
    + ')' + CHAR(13)
    + ISNULL((SELECT (
        SELECT CHAR(13) +
             'ALTER TABLE [' + @schema_for_new_table + '].[' + @name_for_new_table + '] WITH' 
            + CASE WHEN fk.is_not_trusted = 1 
                THEN ' NOCHECK' 
                ELSE ' CHECK' 
              END + 
              ' ADD CONSTRAINT [FK_' + @schema_for_new_table + '_' + @name_for_new_table + '_' + fk.name  + '] FOREIGN KEY(' 
              + STUFF((
                SELECT ', [' + k.cname + ']'
                FROM fk_columns k
                WHERE k.constraint_object_id = fk.[object_id]
                FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, '')
               + ')' +
              ' REFERENCES [' + SCHEMA_NAME(ro.[schema_id]) + '].[' + ro.name + '] ('
              + STUFF((
                SELECT ', [' + k.rcname + ']'
                FROM fk_columns k
                WHERE k.constraint_object_id = fk.[object_id]
                FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, '')
               + ')'
            + CASE 
                WHEN fk.delete_referential_action = 1 THEN ' ON DELETE CASCADE' 
                WHEN fk.delete_referential_action = 2 THEN ' ON DELETE SET NULL'
                WHEN fk.delete_referential_action = 3 THEN ' ON DELETE SET DEFAULT' 
                ELSE '' 
              END
            + CASE 
                WHEN fk.update_referential_action = 1 THEN ' ON UPDATE CASCADE'
                WHEN fk.update_referential_action = 2 THEN ' ON UPDATE SET NULL'
                WHEN fk.update_referential_action = 3 THEN ' ON UPDATE SET DEFAULT'  
                ELSE '' 
              END 
            + CHAR(13) + 'ALTER TABLE [' + @schema_for_new_table + '].[' + @name_for_new_table + '] CHECK CONSTRAINT [FK_' + @schema_for_new_table + '_' + @name_for_new_table + '_' + fk.name  + ']' + CHAR(13)
        FROM sys.foreign_keys fk WITH (NOWAIT)
        JOIN sys.objects ro WITH (NOWAIT) ON ro.[object_id] = fk.referenced_object_id
        WHERE fk.parent_object_id IN (SELECT t.[object_id] FROM tbl t)
        FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)')), '')
    + ISNULL(((SELECT
         CHAR(13) + 'CREATE' + CASE WHEN i.is_unique = 1 THEN ' UNIQUE' ELSE '' END + ' NONCLUSTERED INDEX [IX_' + @schema_for_new_table + '_' + @name_for_new_table + '_' + i.name + '] ON [' + @schema_for_new_table + '].[' + @name_for_new_table + '] (' +
                STUFF((
                SELECT ', [' + c.name + ']' + CASE WHEN c.is_descending_key = 1 THEN ' DESC' ELSE ' ASC' END
                FROM index_column c
                WHERE c.is_included_column = 0
                    AND c.index_id = i.index_id
                FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, '') + ')'  
                + ISNULL(CHAR(13) + 'INCLUDE (' + 
                    STUFF((
                    SELECT ', [' + c.name + ']'
                    FROM index_column c
                    WHERE c.is_included_column = 1
                        AND c.index_id = i.index_id
                    FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)'), 1, 2, '') + ')', '')  + CHAR(13)
        FROM sys.indexes i WITH (NOWAIT)
        WHERE i.[object_id] IN (SELECT t.[object_id] FROM tbl t)
            AND i.is_primary_key = 0
            AND i.[type] = 2
        FOR XML PATH(N''), TYPE, ROOT).value('root[1]', 'NVARCHAR(MAX)')
    ), '')

PRINT @SQL
--EXEC sys.sp_executesql @SQL

输出：

CREATE TABLE [dbo].[test1_new]
(
      [company_id] INT NOT NULL
    , [email] NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AS NULL
    , [staff_name] NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AS NULL
    , CONSTRAINT [PK_dbo_test1_new] PRIMARY KEY ([company_id] ASC)
)