我有一个SQL Server数据库,我想知道它有什么列和类型。我更喜欢通过查询而不是使用像Enterprise Manager这样的GUI来实现这一点。有办法做到这一点吗?


当前回答

use

SELECT COL_LENGTH('tablename', 'colname')

其他的解决方法对我都不起作用。

其他回答

你可以使用sp_help 'TableName'

我在t-sql中写了一个sql* + DESC(RIBE),比如select(显示列注释):

USE YourDB
GO

DECLARE @objectName NVARCHAR(128) = 'YourTable';

SELECT
  a.[NAME]
 ,a.[TYPE]
 ,a.[CHARSET]
 ,a.[COLLATION]
 ,a.[NULLABLE]
 ,a.[DEFAULT]
 ,b.[COMMENTS]
-- ,a.[ORDINAL_POSITION]
FROM
  (
    SELECT
      COLUMN_NAME                                     AS [NAME]
     ,CASE DATA_TYPE
        WHEN 'char'       THEN DATA_TYPE  + '(' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + ')'
        WHEN 'numeric'    THEN DATA_TYPE  + '(' + CAST(NUMERIC_PRECISION AS VARCHAR) + ', ' + CAST(NUMERIC_SCALE AS VARCHAR) + ')'
        WHEN 'nvarchar'   THEN DATA_TYPE  + '(' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + ')'
        WHEN 'varbinary'  THEN DATA_TYPE + '(' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + ')'
        WHEN 'varchar'    THEN DATA_TYPE   + '(' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + ')'
        ELSE DATA_TYPE
      END                                             AS [TYPE]
     ,CHARACTER_SET_NAME                              AS [CHARSET]
     ,COLLATION_NAME                                  AS [COLLATION]
     ,IS_NULLABLE                                     AS [NULLABLE]
     ,COLUMN_DEFAULT                                  AS [DEFAULT]
     ,ORDINAL_POSITION
    FROM   
      INFORMATION_SCHEMA.COLUMNS
    WHERE
      TABLE_NAME = @objectName
  ) a
  FULL JOIN
  (
   SELECT
     CAST(value AS NVARCHAR)                        AS [COMMENTS]
    ,CAST(objname AS NVARCHAR)                      AS [NAME]
   FROM
     ::fn_listextendedproperty ('MS_Description', 'user', 'dbo', 'table', @objectName, 'column', default)
  ) b
  ON a.NAME COLLATE YourCollation = b.NAME COLLATE YourCollation
ORDER BY
  a.[ORDINAL_POSITION];

上面提到的select可以在一个系统标记的存储过程中使用,并且可以从你实例的任何数据库中以简单的方式调用它:

USE master;
GO

IF OBJECT_ID('sp_desc', 'P') IS NOT NULL
  DROP PROCEDURE sp_desc
GO

CREATE PROCEDURE sp_desc (
  @tableName  nvarchar(128)
) AS
BEGIN
  DECLARE @dbName       sysname;
  DECLARE @schemaName   sysname;
  DECLARE @objectName   sysname;
  DECLARE @objectID     int;
  DECLARE @tmpTableName varchar(100);
  DECLARE @sqlCmd       nvarchar(4000);

  SELECT @dbName = PARSENAME(@tableName, 3);
  IF @dbName IS NULL SELECT @dbName = DB_NAME();

  SELECT @schemaName = PARSENAME(@tableName, 2);
  IF @schemaName IS NULL SELECT @schemaName = SCHEMA_NAME();

  SELECT @objectName = PARSENAME(@tableName, 1);
  IF @objectName IS NULL
    BEGIN
      PRINT 'Object is missing from your function call!';
      RETURN;
    END;

  SELECT @objectID = OBJECT_ID(@dbName + '.' + @schemaName + '.' + @objectName);
  IF @objectID IS NULL
    BEGIN
      PRINT 'Object [' + @dbName + '].[' + @schemaName + '].[' + @objectName + '] does not exist!';
      RETURN;
    END;

  SELECT @tmpTableName = '#tmp_DESC_' + CAST(@@SPID AS VARCHAR) + REPLACE(REPLACE(REPLACE(REPLACE(CAST(CONVERT(CHAR, GETDATE(), 121) AS VARCHAR), '-', ''), ' ', ''), ':', ''), '.', '');
  --PRINT @tmpTableName;
  SET @sqlCmd = '
    USE ' + @dbName + '
    CREATE TABLE ' + @tmpTableName + ' (
      [NAME]              nvarchar(128) NOT NULL
     ,[TYPE]              varchar(50)
     ,[CHARSET]           varchar(50)
     ,[COLLATION]         varchar(50)
     ,[NULLABLE]          varchar(3)
     ,[DEFAULT]           nvarchar(4000)
     ,[COMMENTS]          nvarchar(3750));

    INSERT INTO ' + @tmpTableName + '
    SELECT
      a.[NAME]
     ,a.[TYPE]
     ,a.[CHARSET]
     ,a.[COLLATION]
     ,a.[NULLABLE]
     ,a.[DEFAULT]
     ,b.[COMMENTS]
    FROM
      (
        SELECT
          COLUMN_NAME                                     AS [NAME]
         ,CASE DATA_TYPE
            WHEN ''char''      THEN DATA_TYPE + ''('' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + '')''
            WHEN ''numeric''   THEN DATA_TYPE + ''('' + CAST(NUMERIC_PRECISION AS VARCHAR) + '', '' + CAST(NUMERIC_SCALE AS VARCHAR) + '')''
            WHEN ''nvarchar''  THEN DATA_TYPE + ''('' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + '')''
            WHEN ''varbinary'' THEN DATA_TYPE + ''('' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + '')''
            WHEN ''varchar''   THEN DATA_TYPE + ''('' + CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR) + '')''
            ELSE DATA_TYPE
          END                                             AS [TYPE]
         ,CHARACTER_SET_NAME                              AS [CHARSET]
         ,COLLATION_NAME                                  AS [COLLATION]
         ,IS_NULLABLE                                     AS [NULLABLE]
         ,COLUMN_DEFAULT                                  AS [DEFAULT]
         ,ORDINAL_POSITION
        FROM   
          INFORMATION_SCHEMA.COLUMNS
        WHERE   
          TABLE_NAME = ''' + @objectName + '''
      ) a
      FULL JOIN
      (
         SELECT
           CAST(value AS NVARCHAR)                        AS [COMMENTS]
          ,CAST(objname AS NVARCHAR)                      AS [NAME]
         FROM
           ::fn_listextendedproperty (''MS_Description'', ''user'', ''' + @schemaName + ''', ''table'', ''' + @objectName + ''', ''column'', default)
      ) b
      ON a.NAME COLLATE Hungarian_CI_AS = b.NAME COLLATE Hungarian_CI_AS
    ORDER BY
      a.[ORDINAL_POSITION];

    SELECT * FROM ' + @tmpTableName + ';'

    --PRINT @sqlCmd;

    EXEC sp_executesql @sqlCmd;
    RETURN;
END;
GO

EXEC sys.sp_MS_marksystemobject sp_desc
GO

执行过程类型:

EXEC sp_desc 'YourDB.YourSchema.YourTable';

如果你想获取当前数据库(和模式)简单类型对象的描述:

EXEC sp_desc 'YourTable';

因为sp_desc是一个系统标记的过程,你甚至可以留下exec命令(无论如何不推荐):

sp_desc 'YourTable';

use

SELECT COL_LENGTH('tablename', 'colname')

其他的解决方法对我都不起作用。

下面的查询将提供类似于python、Pandas库中的info()函数的输出。

USE [Database_Name]

IF OBJECT_ID('tempdo.dob.#primary_key', 'U') IS NOT NULL DROP TABLE #primary_key

SELECT 
CONS_T.TABLE_CATALOG,
CONS_T.TABLE_SCHEMA,
CONS_T.TABLE_NAME,
CONS_C.COLUMN_NAME,
CONS_T.CONSTRAINT_TYPE,
CONS_T.CONSTRAINT_NAME
INTO  #primary_key
FROM
INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS CONS_T 
JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE AS CONS_C ON CONS_C.CONSTRAINT_NAME= CONS_T.CONSTRAINT_NAME


SELECT
SMA.name AS [Schema Name],
ST.name AS [Table Name],
SC.column_id AS [Column Order],
SC.name AS [Column Name],
PKT.CONSTRAINT_TYPE, 
PKT.CONSTRAINT_NAME, 
SC.system_type_id,
STP.name AS [Data Type],
SC.max_length,
SC.precision, 
SC.scale, 
SC.is_nullable, 
SC.is_masked
FROM sys.tables  AS ST
JOIN sys.schemas AS SMA ON SMA.schema_id = ST.schema_id
JOIN sys.columns AS SC ON SC.object_id = ST.object_id 
JOIN sys.types AS STP ON STP.system_type_id = SC.system_type_id
LEFT JOIN #primary_key AS PKT ON PKT.TABLE_SCHEMA = SMA.name
                                 AND PKT.TABLE_NAME = ST.name
                                 AND PKT.COLUMN_NAME = SC.name
ORDER BY ST.name ASC, SMA.name ASC

除了上述问题,如果我们在DB中有像db_name.dbo这样的表。Table_name,我们可以使用以下步骤

连接DB 使用db_name; 使用EXEC sp_help,不要忘记将表名设置为'dbo。表名'如果你有dbo作为schema。 Exec sp_help 'dbo.table_name'

这应该有用!