sql - T-SQL:如何通过列的 ID 获取用户定义的数据类型？

Question

我有一个这样的查询:

SELECT TABLE_NAME, COLUMN_NAME, IS_NULLABLE, DATA_TYPE
FROM MY_DB.INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME = 'OrderId'
ORDER BY TABLE_NAME
GO

OrderId 列是用户定义的数据类型。但查询中的 DATA_TYPE 会显示底层系统类型(即 bigint)。如何显示用户定义的类型名称？

Answer 1

您可以更改Where子句:

SELECT 
    c.name as ColumneName, 
    c.colid As ColumnOrder, 
    st.name as UserType,
    bt.name as BaseType
FROM dbo.syscolumns c
INNER JOIN dbo.systypes st ON st.xusertype = c.xusertype
INNER JOIN dbo.systypes bt ON bt.xusertype = c.xtype
WHERE c.id = OBJECT_ID('TableName')
ORDER BY c.colid

编辑 - 更完整的版本 - 享受!!

SELECT 
    OBJECT_NAME(c.id) as TableName,
    c.name as ColumnName, 
    c.colid As ColumnOrder, 
    st.name as UserType,
    bt.name as BaseType
FROM 
    dbo.syscolumns c
    INNER JOIN dbo.systypes st ON st.xusertype = c.xusertype
    INNER JOIN dbo.systypes bt ON bt.xusertype = c.xtype
WHERE 
    OBJECTPROPERTY(c.id,'ISTABLE') = 1
    AND c.name = 'ColumnName'
ORDER BY
    OBJECT_NAME(c.id), 
    c.colid