Tengo una base de datos SQL Server y quiero saber qué columnas y tipos tiene. Prefiero hacer esto a través de una consulta en lugar de usar una GUI como Enterprise Manager. ¿Hay alguna forma de hacer esto?
Tengo una base de datos SQL Server y quiero saber qué columnas y tipos tiene. Prefiero hacer esto a través de una consulta en lugar de usar una GUI como Enterprise Manager. ¿Hay alguna forma de hacer esto?
Respuestas:
Puede usar el procedimiento almacenado sp_columns :
exec sp_columns MyTable
select
encuentran a continuación son mucho más apropiadas para los usuarios de sqlcmd.
Existen algunos métodos para obtener metadatos sobre una tabla:
EXEC sp_help tablename
Devolverá varios conjuntos de resultados, describiendo la tabla, sus columnas y restricciones.
Las INFORMATION_SCHEMA
vistas le darán la información que desea, aunque desafortunadamente tiene que consultar las vistas y unirlas manualmente.
@
es una sintaxis incorrecta sin embargo.
@tablename
es una variable en el ejemplo. El sp funciona en ambos sentidos, con una cadena o el nombre de tabla 'simple' ( exec sp_help Employees
o exec sp_help 'Employees'
)
execute sp_help 'db.sch.your_table
En caso de que no desee utilizar el proceso almacenado, aquí hay una versión de consulta simple
select *
from information_schema.columns
where table_name = 'aspnet_Membership'
order by ordinal_position
Puedes usar el siguiente
sp_help tablename
Ejemplo: sp_help Customer
O use el acceso directo
Ejemplo: Cliente Presione Alt + F1
Ctrl+W
se puede usar para expandir la selección y seleccionar el nombre completo.
Use esta consulta
Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME'
Además de las formas que se muestran en otras respuestas, puede usar
SELECT TOP 0 * FROM table_name
Esto le dará el nombre de cada columna sin resultados, y se completa casi instantáneamente con una sobrecarga mínima.
Simplemente seleccione la tabla y presione Alt+ F1,
mostrará toda la información sobre la tabla, como el nombre de la columna, el tipo de datos, las claves, etc.
Escribí un sql * plus DESC (RIBE) como select (también muestra los comentarios de la columna) en 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 selección mencionada anteriormente se puede usar en un procedimiento almacenado marcado del sistema y se puede llamar desde cualquier base de datos de su instancia de una manera 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
Para ejecutar el tipo de procedimiento:
EXEC sp_desc 'YourDB.YourSchema.YourTable';
Si desea obtener una descripción de un objeto de la base de datos actual (y esquema), escriba simple:
EXEC sp_desc 'YourTable';
Como sp_desc es un procedimiento marcado por el sistema, también puede dejar el comando exec (no recomendado de todos modos):
sp_desc 'YourTable';
El equivalente de SQL Server al describe
comando de Oracle es el proceso almacenadosp_help
El describe
comando le brinda información sobre los nombres de columna, tipos, longitud, etc.
En SQL Server, supongamos que desea describir una tabla 'mytable' en el esquema 'myschema' en la base de datos 'mydb', puede hacer lo siguiente:
USE mydb;
exec sp_help 'myschema.mytable';
Puede usar sp_help 'TableName'
El problema con esas respuestas es que te falta la información clave. Si bien esto es un poco desordenado, esta es una versión rápida que se me ocurrió para asegurarme de que contenga la misma información que muestra MySQL Describe.
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')
Este es el código que uso dentro de EntityFramework Reverse POCO Generator
(disponible aquí )
Tabla 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')
SQL de clave externa:
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
Propiedades extendidas:
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
Me gusta este formato:
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
Entonces he usado esto:
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>';
Si está utilizando FirstResponderKit del equipo de Brent Ozar, también puede ejecutar esta consulta:
exec sp_blitzindex @tablename='MyTable'
Devolverá toda la información sobre la tabla:
Por supuesto, no es un sistema y stp no tan universal como sp_help o sp_columns , pero devuelve toda la información posible sobre su tabla y creo que vale la pena crearla en su entorno y mencionarla aquí.
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