Question

我正在尝试获取具有特定类型的列的名称（因此我可以动态查询结果）。下面的代码似乎让我接近（因为类型= 56代表int）但它似乎是不正确的。更不用说我没能找到从类型到int表示的良好映射。

SELECT c.system_type_id as type
FROM SYS.COLUMNS c
JOIN SYS.TABLES t ON c.object_id = t.object_id   
WHERE t.name = 'MyTableName'

由于

Answer 1

您可以在sys.types目录视图中找到类型的映射：

SELECT c.name as column_name, ty.name as type_name
FROM SYS.COLUMNS c
JOIN SYS.TABLES t ON c.object_id = t.object_id   
JOIN SYS.TYPES ty ON c.system_type_id = ty.system_type_id
WHERE t.name = 'MyTableName'

Answer 2

SELECT 
    c.name 'Column Name',
    t.Name 'Data type'
FROM    
    sys.columns c INNER JOIN 
    sys.types t ON c.user_type_id = t.user_type_id
LEFT OUTER JOIN     sys.index_columns ic ON ic.object_id = c.object_id AND ic.column_id = c.column_id
LEFT OUTER JOIN sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id
WHERE
    c.object_id = OBJECT_ID('TableName')

Answer 3

假设您正在使用SQL Server，您可以执行以下操作;

DECLARE @DataType varchar(20); SET @DataType = 'int'

SELECT
    o.name TableName
    ,c.name ColumnName
    ,t.name ColumnType
    ,t.max_length ColumnLength
FROM sys.columns c
JOIN sys.objects o
    ON c.object_id = o.object_id
JOIN sys.types t
    ON c.user_type_id = t.user_type_id 
WHERE t.name LIKE '%' + @DataType + '%'
    AND o.type_desc = 'USER_TABLE'

只需更改变量中的数据类型，它就会显示如下列表

TableName   ColumnName  ColumnType  ColumnLength
Employees   empid       int         4
Employees   mgrid       int         4
Suppliers   supplierid  int         4
Categories  categoryid  int         4
Products    productid   int         4
Products    supplierid  int         4

您可以修改此项以添加表格名称，如果这是您想要做的事情。

T-SQL获取特定类型的列

3 个答案: