是否有SQL语句可以返回表中列的类型?


当前回答

使用此查询获取Schema, Table, Column,Type, max_length, is_nullable

SELECT QUOTENAME(SCHEMA_NAME(tb.[schema_id])) AS 'Schema'
    ,QUOTENAME(OBJECT_NAME(tb.[OBJECT_ID])) AS 'Table'
    ,C.NAME as 'Column'
    ,T.name AS 'Type'
    ,C.max_length
    ,C.is_nullable
FROM SYS.COLUMNS C INNER JOIN SYS.TABLES tb ON tb.[object_id] = C.[object_id]
    INNER JOIN SYS.TYPES T ON C.system_type_id = T.user_type_id
WHERE tb.[is_ms_shipped] = 0
ORDER BY tb.[Name]

其他回答

如果你正在使用MySQL,你可以试试

SHOW COLUMNS FROM `tbl_name`;

在dev.mysql.com上显示列

否则你应该能做到

DESCRIBE `tbl_name`;

对于Spark SQL:

DESCRIBE [db_name.]table_name column_name

在oracle SQL中,你可以这样做:

SELECT
    DATA_TYPE
FROM
    all_tab_columns 
WHERE
    table_name = 'TABLE NAME' -- in uppercase
AND column_name = 'COLUMN NAME' -- in uppercase

在TSQL中最简单的方法是:

SELECT COLUMN_NAME, DATA_TYPE 
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE TABLE_NAME = 'yourTableName'

从SQL Server 2012开始:

SELECT * FROM sys.dm_exec_describe_first_result_set( N'SELECT * FROM [my].[Table]', NULL, 0 );