sqlserver通过语句 根据表生成建表语句及索引和约束的语句

在 SQL Server 中，可以使用以下语句生成表的建表语句：

SELECT 
    'CREATE TABLE ' + 
    schema_name(tab.schema_id) + '.' + tab.name + '(' + 
    column_list + 
    CASE WHEN EXISTS (SELECT * FROM sys.indexes WHERE object_id = tab.object_id AND is_primary_key = 1) THEN ', CONSTRAINT ' + pk.name  + ' PRIMARY KEY CLUSTERED (' + pk_col_list + ')' ELSE '' END + 
    ')' + 
    CASE WHEN tab.create_date <> tab.modify_date THEN '/* Created: ' + CONVERT(NVARCHAR(30),tab.create_date,120) + ', Modified: ' + CONVERT(NVARCHAR(30),tab.modify_date,120) + ' */' ELSE '' END AS create_table_script
FROM sys.tables AS tab
CROSS APPLY (SELECT 
    STUFF((SELECT 
        ', ' + col.name + ' ' + sys.types.name + 
        CASE WHEN col.is_nullable = 0 THEN ' NOT NULL' ELSE '' END + 
        CASE WHEN defn.definition IS NOT NULL THEN ' DEFAULT' + defn.definition ELSE '' END
        FROM sys.columns AS col
        JOIN sys.types ON col.user_type_id = sys.types.user_type_id
        LEFT JOIN sys.default_constraints AS defn ON col.default_object_id = defn.object_id
        WHERE col.object_id = tab.object_id
        ORDER BY col.column_id
        FOR XML PATH(''), TYPE).value('.', 'nvarchar(max)'), 1, 2, '')) AS column_list
LEFT JOIN (
    SELECT 
        i.object_id, 
        name, 
        STUFF((SELECT 
            ', ' + col.name 
            FROM sys.index_columns AS ic
            JOIN sys.columns AS col ON ic.column_id = col.column_id AND ic.object_id = col.object_id
            WHERE i.object_id = ic.object_id AND i.index_id = ic.index_id
            ORDER BY ic.key_ordinal
            FOR XML PATH(''), TYPE).value('.', 'nvarchar(max)'), 1, 2, '') AS pk_col_list
    FROM sys.indexes AS i
    WHERE is_primary_key = 1
) AS pk ON tab.object_id = pk.object_id

此语句将生成所有表的 CREATE TABLE 语句和主键约束。如果还需要生成索引和其他约束的语句，可以参考以下示例：

SELECT
    'CREATE ' + 
    CASE WHEN is_unique_constraint = 1 THEN 'UNIQUE ' ELSE '' END + 
    'INDEX ' + 
    ix.name + ' ON ' + 
    schema_name(tab.schema_id) + '.' + tab.name + '(' + 
    STUFF((SELECT 
        ', ' + col.name + 
        CASE WHEN ic.is_descending_key = 1 THEN ' DESC' ELSE '' END
        FROM sys.index_columns AS ic
        JOIN sys.columns AS col ON ic.column_id = col.column_id AND ic.object_id = col.object_id
        WHERE ic.object_id = ix.object_id AND ic.index_id = ix.index_id
        ORDER BY ic.key_ordinal
        FOR XML PATH(''), TYPE).value('.', 'nvarchar(max)'), 1, 2, '') + 
    ')' + 
    CASE WHEN ix.create_date <> ix.modify_date THEN '/* Created: ' + CONVERT(NVARCHAR(30),ix.create_date,120) + ', Modified: ' + CONVERT(NVARCHAR(30),ix.modify_date,120) + ' */' ELSE '' END AS create_index_script
FROM sys.indexes AS ix
JOIN sys.tables AS tab ON ix.object_id = tab.object_id
WHERE is_primary_key = 0 AND is_unique_constraint = 0 AND is_disabled = 0 AND ix.type <> 0

此语句将生成所有非聚集索引的 CREATE INDEX 语句。如果还需要生成其他约束的语句，可以使用类似的方法查询 sys.objects 和其他系统视图。