Quel est l'équivalent de «décrire la table» dans SQL Server?

J'ai une base de données SQL Server et je veux savoir quelles colonnes et quels types elle contient. Je préfère le faire via une requête plutôt que d'utiliser une interface graphique comme Enterprise Manager. Y a-t-il un moyen de faire cela?

Vous pouvez utiliser la procédure stockée sp_columns :

exec sp_columns MyTable

Il existe quelques méthodes pour obtenir des métadonnées sur une table:

EXEC sp_help tablename

Renvoie plusieurs jeux de résultats décrivant le tableau, ses colonnes et ses contraintes.

Les INFORMATION_SCHEMAvues vous donneront les informations que vous souhaitez, mais malheureusement, vous devez interroger les vues et les joindre manuellement.

Juste au cas où vous ne souhaitez pas utiliser le proc stocké, voici une version de requête simple

select * 
  from information_schema.columns 
 where table_name = 'aspnet_Membership'
 order by ordinal_position

Vous pouvez utiliser les éléments suivants

sp_help tablename

Exemple: client sp_help

OU Utilisez un raccourci

• sélectionnez le tableau appuyez sur Alt + F1

Exemple: Client Appuyez sur Alt + F1

Utilisez cette requête

Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME'

En plus des moyens indiqués dans d'autres réponses, vous pouvez utiliser

SELECT TOP 0 * FROM table_name

Cela vous donnera le nom de chaque colonne sans résultat, et se termine presque instantanément avec un minimum de frais généraux.

Veuillez utiliser la requête SQL suivante; cela a fonctionné pour mon cas.

select * FROM   INFORMATION_SCHEMA.Columns where table_name = 'tablename';

Sélectionnez simplement le tableau et appuyez sur Alt+ F1,

il affichera toutes les informations sur la table comme le nom de la colonne, le type de données, les clés, etc.

J'ai écrit un sql * plus DESC (RIBE) comme select (affiche également les commentaires de la colonne) dans t-sql:

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];

La sélection mentionnée ci-dessus peut être utilisée dans une procédure stockée marquée par le système et peut être appelée à partir de n'importe quelle base de données de votre instance de manière simple:

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

Pour exécuter le type de procédure:

EXEC sp_desc 'YourDB.YourSchema.YourTable';

Si vous souhaitez obtenir une description d'un objet du type simple de la base de données (et du schéma) actuel:

EXEC sp_desc 'YourTable';

Comme sp_desc est une procédure marquée par le système, vous pouvez même laisser la commande exec également (non recommandée de toute façon):

sp_desc 'YourTable';

L'équivalent SQL Server de la describecommande Oracle est le proc stockésp_help

La describecommande vous donne les informations sur les noms de colonne, les types, la longueur, etc.

Dans SQL Server, disons que vous voulez décrire une table 'mytable' dans le schéma 'myschema' dans la base de données 'mydb', vous pouvez faire ce qui suit:

USE mydb;
exec sp_help 'myschema.mytable';

Vous pouvez utiliser le sp_help 'TableName'

Le problème avec ces réponses est que vous manquez les informations clés. Bien que ce soit un peu compliqué, c'est une version rapide que j'ai trouvée pour m'assurer qu'elle contient les mêmes informations que MySQL Describe affiche.

Select SC.name AS 'Field', ISC.DATA_TYPE AS 'Type', ISC.CHARACTER_MAXIMUM_LENGTH AS 'Length', SC.IS_NULLABLE AS 'Null', I.is_primary_key AS 'Key', SC.is_identity AS 'Identity'
From sys.columns AS SC 
LEFT JOIN sys.index_columns AS IC
ON IC.object_id = OBJECT_ID('dbo.Expenses') AND 
IC.column_id = SC.column_id
LEFT JOIN sys.indexes AS I 
ON I.object_id = OBJECT_ID('dbo.Expenses') AND 
IC.index_id = I.index_id
LEFT JOIN information_schema.columns ISC
ON ISC.TABLE_NAME = 'Expenses'
AND ISC.COLUMN_NAME = SC.name
WHERE SC.object_id = OBJECT_ID('dbo.Expenses')

Ceci est le code que j'utilise dans EntityFramework Reverse POCO Generator(disponible ici )

Table SQL:

SELECT  c.TABLE_SCHEMA AS SchemaName,
        c.TABLE_NAME AS TableName,
        t.TABLE_TYPE AS TableType,
        c.ORDINAL_POSITION AS Ordinal,
        c.COLUMN_NAME AS ColumnName,
        CAST(CASE WHEN IS_NULLABLE = 'YES' THEN 1
                  ELSE 0
             END AS BIT) AS IsNullable,
        DATA_TYPE AS TypeName,
        ISNULL(CHARACTER_MAXIMUM_LENGTH, 0) AS [MaxLength],
        CAST(ISNULL(NUMERIC_PRECISION, 0) AS INT) AS [Precision],
        ISNULL(COLUMN_DEFAULT, '') AS [Default],
        CAST(ISNULL(DATETIME_PRECISION, 0) AS INT) AS DateTimePrecision,
        ISNULL(NUMERIC_SCALE, 0) AS Scale,
        CAST(COLUMNPROPERTY(OBJECT_ID(QUOTENAME(c.TABLE_SCHEMA) + '.' + QUOTENAME(c.TABLE_NAME)), c.COLUMN_NAME, 'IsIdentity') AS BIT) AS IsIdentity,
        CAST(CASE WHEN COLUMNPROPERTY(OBJECT_ID(QUOTENAME(c.TABLE_SCHEMA) + '.' + QUOTENAME(c.TABLE_NAME)), c.COLUMN_NAME, 'IsIdentity') = 1 THEN 1
                  WHEN COLUMNPROPERTY(OBJECT_ID(QUOTENAME(c.TABLE_SCHEMA) + '.' + QUOTENAME(c.TABLE_NAME)), c.COLUMN_NAME, 'IsComputed') = 1 THEN 1
                  WHEN DATA_TYPE = 'TIMESTAMP' THEN 1
                  ELSE 0
             END AS BIT) AS IsStoreGenerated,
        CAST(CASE WHEN pk.ORDINAL_POSITION IS NULL THEN 0
                  ELSE 1
             END AS BIT) AS PrimaryKey,
        ISNULL(pk.ORDINAL_POSITION, 0) PrimaryKeyOrdinal,
        CAST(CASE WHEN fk.COLUMN_NAME IS NULL THEN 0
                  ELSE 1
             END AS BIT) AS IsForeignKey
FROM    INFORMATION_SCHEMA.COLUMNS c
        LEFT OUTER JOIN (SELECT u.TABLE_SCHEMA,
                                u.TABLE_NAME,
                                u.COLUMN_NAME,
                                u.ORDINAL_POSITION
                         FROM   INFORMATION_SCHEMA.KEY_COLUMN_USAGE u
                                INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc
                                    ON u.TABLE_SCHEMA = tc.CONSTRAINT_SCHEMA
                                       AND u.TABLE_NAME = tc.TABLE_NAME
                                       AND u.CONSTRAINT_NAME = tc.CONSTRAINT_NAME
                         WHERE  CONSTRAINT_TYPE = 'PRIMARY KEY') pk
            ON c.TABLE_SCHEMA = pk.TABLE_SCHEMA
               AND c.TABLE_NAME = pk.TABLE_NAME
               AND c.COLUMN_NAME = pk.COLUMN_NAME
        LEFT OUTER JOIN (SELECT DISTINCT
                                u.TABLE_SCHEMA,
                                u.TABLE_NAME,
                                u.COLUMN_NAME
                         FROM   INFORMATION_SCHEMA.KEY_COLUMN_USAGE u
                                INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc
                                    ON u.TABLE_SCHEMA = tc.CONSTRAINT_SCHEMA
                                       AND u.TABLE_NAME = tc.TABLE_NAME
                                       AND u.CONSTRAINT_NAME = tc.CONSTRAINT_NAME
                         WHERE  CONSTRAINT_TYPE = 'FOREIGN KEY') fk
            ON c.TABLE_SCHEMA = fk.TABLE_SCHEMA
               AND c.TABLE_NAME = fk.TABLE_NAME
               AND c.COLUMN_NAME = fk.COLUMN_NAME
        INNER JOIN INFORMATION_SCHEMA.TABLES t
            ON c.TABLE_SCHEMA = t.TABLE_SCHEMA
               AND c.TABLE_NAME = t.TABLE_NAME
WHERE c.TABLE_NAME NOT IN ('EdmMetadata', '__MigrationHistory')

Clé étrangère SQL:

SELECT  FK.name AS FK_Table,
        FkCol.name AS FK_Column,
        PK.name AS PK_Table,
        PkCol.name AS PK_Column,
        OBJECT_NAME(f.object_id) AS Constraint_Name,
        SCHEMA_NAME(FK.schema_id) AS fkSchema,
        SCHEMA_NAME(PK.schema_id) AS pkSchema,
        PkCol.name AS primarykey,
        k.constraint_column_id AS ORDINAL_POSITION
FROM    sys.objects AS PK
        INNER JOIN sys.foreign_keys AS f
            INNER JOIN sys.foreign_key_columns AS k
                ON k.constraint_object_id = f.object_id
            INNER JOIN sys.indexes AS i
                ON f.referenced_object_id = i.object_id
                   AND f.key_index_id = i.index_id
            ON PK.object_id = f.referenced_object_id
        INNER JOIN sys.objects AS FK
            ON f.parent_object_id = FK.object_id
        INNER JOIN sys.columns AS PkCol
            ON f.referenced_object_id = PkCol.object_id
               AND k.referenced_column_id = PkCol.column_id
        INNER JOIN sys.columns AS FkCol
            ON f.parent_object_id = FkCol.object_id
               AND k.parent_column_id = FkCol.column_id
ORDER BY FK_Table, FK_Column

Propriétés étendues:

SELECT  s.name AS [schema],
        t.name AS [table],
        c.name AS [column],
        value AS [property]
FROM    sys.extended_properties AS ep
        INNER JOIN sys.tables AS t
            ON ep.major_id = t.object_id
        INNER JOIN sys.schemas AS s
            ON s.schema_id = t.schema_id
        INNER JOIN sys.columns AS c
            ON ep.major_id = c.object_id
               AND ep.minor_id = c.column_id
WHERE   class = 1
ORDER BY t.name

utilisation

SELECT COL_LENGTH('tablename', 'colname')

Aucune autre solution n'a fonctionné pour moi.

J'aime ce format:

name     DataType      Collation             Constraints         PK  FK          Comment

id       int                                 NOT NULL IDENTITY   PK              Order Line Id
pid      int                                 NOT NULL                tbl_orders  Order Id
itemCode varchar(10)   Latin1_General_CI_AS  NOT NULL                            Product Code

J'ai donc utilisé ceci:

DECLARE @tname varchar(100) = 'yourTableName';

SELECT  col.name,

        CASE typ.name
            WHEN 'nvarchar' THEN 'nvarchar('+CAST((col.max_length / 2) as varchar)+')'
            WHEN 'varchar' THEN 'varchar('+CAST(col.max_length as varchar)+')'
            WHEN 'char' THEN 'char('+CAST(col.max_length as varchar)+')'
            WHEN 'nchar' THEN 'nchar('+CAST((col.max_length / 2) as varchar)+')'
            WHEN 'binary' THEN 'binary('+CAST(col.max_length as varchar)+')'
            WHEN 'varbinary' THEN 'varbinary('+CAST(col.max_length as varchar)+')'
            WHEN 'numeric' THEN 'numeric('+CAST(col.precision as varchar)+(CASE WHEN col.scale = 0 THEN '' ELSE ','+CAST(col.scale as varchar) END) +')'
            WHEN 'decimal' THEN 'decimal('+CAST(col.precision as varchar)+(CASE WHEN col.scale = 0 THEN '' ELSE ','+CAST(col.scale as varchar) END) +')'
            ELSE typ.name
            END DataType,

        ISNULL(col.collation_name,'') Collation,

        CASE WHEN col.is_nullable = 0 THEN 'NOT NULL ' ELSE '' END + CASE WHEN col.is_identity = 1 THEN 'IDENTITY' ELSE '' END Constraints,

        ISNULL((SELECT 'PK'
                FROM    sys.key_constraints kc INNER JOIN
                        sys.tables tb ON tb.object_id = kc.parent_object_id INNER JOIN
                        sys.indexes si ON si.name = kc.name INNER JOIN
                        sys.index_columns sic ON sic.index_id = si.index_id AND sic.object_id = si.object_id
                WHERE kc.type = 'PK'
                  AND tb.name = @tname
                  AND sic.column_id = col.column_id),'') PK,

        ISNULL((SELECT (SELECT name FROM sys.tables st WHERE st.object_id = fkc.referenced_object_id)
                FROM    sys.foreign_key_columns fkc INNER JOIN
                        sys.columns c ON c.column_id = fkc.parent_column_id AND fkc.parent_object_id = c.object_id INNER JOIN
                        sys.tables t ON t.object_id = c.object_id
                WHERE t.name = tab.name
                  AND c.name = col.name),'') FK,

        ISNULL((SELECT value
                FROM sys.extended_properties
                WHERE major_id = tab.object_id
                  AND minor_id = col.column_id),'') Comment

FROM sys.columns col INNER JOIN
     sys.tables tab ON tab.object_id = col.object_id INNER JOIN
     sys.types typ ON typ.system_type_id = col.system_type_id
WHERE tab.name = @tname
  AND typ.name != 'sysname'
ORDER BY col.column_id;

SELECT C.COLUMN_NAME, C.IS_NULLABLE, C.DATA_TYPE, TC.CONSTRAINT_TYPE, C.COLUMN_DEFAULT
    FROM INFORMATION_SCHEMA.COLUMNS AS C
    FULL JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE AS CC ON C.COLUMN_NAME = CC.COLUMN_NAME 
    FULL JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS TC ON CC.CONSTRAINT_NAME = TC.CONSTRAINT_NAME
WHERE C.TABLE_NAME = '<Table Name>';

Exemple de sortie

Si vous utilisez FirstResponderKit de l'équipe Brent Ozar, vous pouvez également exécuter cette requête:

exec sp_blitzindex @tablename='MyTable'

Il renverra toutes les informations sur la table:

• index avec leurs statistiques d'utilisation (lectures, écritures, verrous, etc.), l'espace utilisé et autres
• index manquants
• Colonnes
• clés étrangères
• contenu des statistiques

Bien sûr, ce n'est pas un système et pas un stp aussi universel comme sp_help ou sp_columns , mais il renvoie toutes les informations possibles sur votre table et je pense que cela vaut la peine de le créer dans votre environnement et de le mentionner ici.

Double-cliquez simplement sur le nom de la table et appuyez sur Alt + F1

CREATE PROCEDURE [dbo].[describe] 
( 
@SearchStr nvarchar(max) 
) 
AS 
BEGIN 
SELECT  
    CONCAT([COLUMN_NAME],' ',[DATA_TYPE],' ',[CHARACTER_MAXIMUM_LENGTH],' ', 
    (SELECT CASE [IS_NULLABLE] WHEN 'NO' THEN 'NOT NULL' ELSE 'NULL' END),
    (SELECT CASE WHEN [COLUMN_DEFAULT] IS NULL THEN '' ELSE CONCAT(' DEFAULT ',[COLUMN_DEFAULT]) END)
    ) AS DESCRIPTION
    FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME LIKE @SearchStr
END