Was ist das Äquivalent von 'beschreiben' in SQL Server?
Ich habe eine SQL Server-Datenbank und möchte wissen, welche Spalten und Typen es hat. Ich würde es vorziehen, dies über eine Abfrage zu tun, anstatt eine GUI wie Enterprise Manager zu verwenden. Gibt es eine Möglichkeit, dies zu tun?
Sie können die Prozedur sp_columns gespeichert verwenden:
exec sp_columns MyTable
Es gibt einige Methoden, um Metadaten zu einer Tabelle abzurufen:
EXEC sp_help tablename
Gibt mehrere Ergebnismengen zurück, die die Tabelle, ihre Spalten und Einschränkungen beschreiben.
Die INFORMATION_SCHEMA-Ansichten geben Ihnen die gewünschten Informationen. Leider müssen Sie die Ansichten abfragen und manuell verknüpfen.
Für den Fall, dass Sie keine gespeicherte Prozedur verwenden möchten, haben wir eine einfache Abfrageversion
select *
from information_schema.columns
where table_name = 'aspnet_Membership'
order by ordinal_position
Verwenden Sie diese Abfrage
Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME'
Sie können folgendes verwenden
sp_help tablename
Beispiel: Sp_help Kunde
ODER Verknüpfung verwenden
- wählen Sie die Tabelle aus, drücken Sie Alt + F1
Beispiel: Kunde Drücken Sie Alt + F1
Einfach Tisch auswählen und drücken Alt+F1,
es werden alle Informationen zu Tabellen wie Spaltenname, Datentyp, Schlüssel usw. angezeigt.
Bitte verwenden Sie die folgende SQL-Abfrage. das hat für meinen Fall funktioniert.
select * FROM INFORMATION_SCHEMA.Columns where table_name = 'tablename';
Zusätzlich zu den in anderen Antworten dargestellten Möglichkeiten können Sie verwenden
SELECT TOP 0 * FROM table_name
Dadurch erhalten Sie den Namen jeder Spalte ohne Ergebnis und werden fast sofort mit minimalem Aufwand abgeschlossen.
Ich habe ein sql * plus DESC (RIBE) wie select geschrieben (zeigt auch die Spaltenkommentare an) in 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];
Die oben erwähnte Auswahl kann in einer mit System markierten gespeicherten Prozedur verwendet werden und kann auf einfache Weise aus einer beliebigen Datenbank Ihrer Instanz aufgerufen werden:
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
So führen Sie den Prozedurtyp aus:
EXEC sp_desc 'YourDB.YourSchema.YourTable';
Wenn Sie eine Beschreibung eines Objekts der aktuellen Datenbank (und des Schemas) erhalten möchten, geben Sie einfach den folgenden Typ ein:
EXEC sp_desc 'YourTable';
Da sp_desc eine vom System markierte Prozedur ist, können Sie auch den exec-Befehl verlassen (sowieso nicht empfohlen):
sp_desc 'YourTable';
Dies ist der Code, den ich im EntityFramework Reverse POCO Generator verwende (verfügbar hier )
Tabelle 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')
Fremdschlüssel-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
Erweiterte Eigenschaften:
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
Sie können die sp_help 'TableName' verwenden.
Das Problem bei diesen Antworten ist, dass Sie die Schlüsseldaten verpassen. Dies ist zwar ein bisschen chaotisch, dies ist jedoch eine schnelle Version, die ich mir vorgestellt habe, um sicherzustellen, dass sie die gleichen Informationen enthält, die MySQL Describe anzeigt.
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')
Der SQL Server, der dem describe-Befehl von Oracle entspricht, ist der gespeicherte proc sp_help
Mit dem Befehl describe erhalten Sie Informationen zu Spaltennamen, -typen, -längen usw.
Angenommen, Sie möchten in SQL Server eine Tabelle 'mytable' im Schema 'myschema' in der Datenbank 'mydb' beschreiben. Sie haben folgende Möglichkeiten:
USE mydb;
exec sp_help 'myschema.mytable';
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
benutzen
SELECT COL_LENGTH('tablename', 'colname')
Keine andere Lösung funktionierte für mich.
Ich mag dieses 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
Also habe ich das benutzt:
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;