如何从SQL Server表对象生成类?

我说的不是使用ORM。我只需要创建实体(简单类)。喜欢的东西:

    public class Person 
    {
        public string Name { get;set; }
        public string Phone { get;set; }
    }

给定一个表,比如:

+----+-------+----------------+
| ID | Name  |     Phone      |
+----+-------+----------------+
|  1 | Alice | (555) 555-5550 |
|  2 | Bob   | (555) 555-5551 |
|  3 | Cathy | (555) 555-5552 |
+----+-------+----------------+



当前回答

要打印NULLABLE属性,请使用此命令。 它对Alex Aza的CASE语句块脚本进行了轻微修改。

declare @TableName sysname = 'TableName'
declare @result varchar(max) = 'public class ' + @TableName + '
{'

select @result = @result + '
    public ' + ColumnType + ' ' + ColumnName + ' { get; set; }
'
from
(
    select 
        replace(col.name, ' ', '_') ColumnName,
        column_id,
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            when 'char' then 'string'
            when 'date' then 'DateTime'
            when 'datetime' then 'DateTime'
            when 'datetime2' then 'DateTime'
            when 'datetimeoffset' then 'DateTimeOffset'
            when 'decimal' then 'decimal'
            when 'float' then 'float'
            when 'image' then 'byte[]'
            when 'int' then 'int'
            when 'money' then 'decimal'
            when 'nchar' then 'char'
            when 'ntext' then 'string'
            when 'numeric' then 'decimal'
            when 'nvarchar' then 'string'
            when 'real' then 'double'
            when 'smalldatetime' then 'DateTime'
            when 'smallint' then 'short'
            when 'smallmoney' then 'decimal'
            when 'text' then 'string'
            when 'time' then 'TimeSpan'
            when 'timestamp' then 'DateTime'
            when 'tinyint' then 'byte'
            when 'uniqueidentifier' then 'Guid'
            when 'varbinary' then 'byte[]'
            when 'varchar' then 'string'
            else 'UNKNOWN_' + typ.name
        end + 
        CASE
            WHEN col.is_nullable=1 AND
                 typ.name NOT IN (
                     'binary', 'varbinary', 'image',
                     'text', 'ntext',
                     'varchar', 'nvarchar', 'char', 'nchar')
            THEN '?'
            ELSE '' END AS [ColumnType]
    from sys.columns col
        join sys.types typ on
            col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id 
    where object_id = object_id(@TableName)
) t
order by column_id

set @result = @result  + '
}'

print @result

其他回答

从Postgres DB生成

DO $$ DECLARE v_tabela varchar; DECLARE v_cursor_colunas record; DECLARE v_nome_coluna varchar; DECLARE v_classe VARCHAR; DECLARE v_tipo VARCHAR; DECLARE v_schema_name VARCHAR; BEGIN v_schema_name := 'my-schema'; v_tabela := 'my-table'; select table_name INTO v_tabela from information_schema.tables where table_schema = v_schema_name and table_type = 'BASE TABLE' and table_name = v_tabela; v_classe := E'\r\n' || 'public class ' || v_tabela || ' {' || E'\r\n'; FOR v_cursor_colunas IN SELECT column_name as coluna, is_nullable as isnull, data_type as tipo, character_maximum_length as tamanho FROM information_schema.columns WHERE table_schema = v_schema_name AND table_name = v_tabela LOOP IF v_cursor_colunas.tipo='character varying' THEN v_tipo:= 'string'; ELSIF v_cursor_colunas.tipo='character' and v_cursor_colunas.tamanho=1 THEN v_tipo:= 'char'; ELSIF v_cursor_colunas.tipo='character' and v_cursor_colunas.tamanho<>1 THEN v_tipo:= 'string'; ELSIF v_cursor_colunas.tipo like 'timestamp%' THEN v_tipo:= 'DateTime'; IF v_cursor_colunas.isnull='YES' then v_tipo:= 'DateTime?'; END IF; ELSIF v_cursor_colunas.tipo='boolean' THEN v_tipo:= 'bool'; IF v_cursor_colunas.isnull='YES' then v_tipo:= 'bool?'; END IF; ELSIF v_cursor_colunas.tipo='integer' THEN v_tipo:= 'int'; IF v_cursor_colunas.isnull='YES' then v_tipo:= 'int?'; END IF; ELSIF v_cursor_colunas.tipo='numeric' THEN v_tipo:= 'double'; IF v_cursor_colunas.isnull='YES' then v_tipo:= 'double?'; END IF; ELSIF v_cursor_colunas.tipo='text' THEN v_tipo:= 'string'; ELSE v_tipo:= 'another'; END IF; v_nome_coluna := v_cursor_colunas.coluna; v_classe := v_classe || 'public ' || v_tipo || ' ' || v_cursor_colunas.coluna || ' { get; set; }' || E'\r\n'; END LOOP;

v_class:= v_class || E'\r\n' || '}'; RAISE NOTICE '%', v_class; $ $;

VB版

declare @TableName sysname = 'myTableName'
declare @prop varchar(max)
PRINT 'Public Class ' + @TableName
declare props cursor for
select distinct ' public property ' + ColumnName + ' AS ' + ColumnType AS prop
from ( 
    select  
        replace(col.name, ' ', '_') ColumnName,  column_id, 
        case typ.name  
            when 'bigint' then 'long' 
            when 'binary' then 'byte[]' 
            when 'bit' then 'boolean' 
            when 'char' then 'string' 
            when 'date' then 'DateTime' 
            when 'datetime' then 'DateTime' 
            when 'datetime2' then 'DateTime' 
            when 'datetimeoffset' then 'DateTimeOffset' 
            when 'decimal' then 'decimal' 
            when 'float' then 'float' 
            when 'image' then 'byte[]' 
            when 'int' then 'integer' 
            when 'money' then 'decimal' 
            when 'nchar' then 'char' 
            when 'ntext' then 'string' 
            when 'numeric' then 'decimal' 
            when 'nvarchar' then 'string' 
            when 'real' then 'double' 
            when 'smalldatetime' then 'DateTime' 
            when 'smallint' then 'short' 
            when 'smallmoney' then 'decimal' 
            when 'text' then 'string' 
            when 'time' then 'TimeSpan' 
            when 'timestamp' then 'DateTime' 
            when 'tinyint' then 'byte' 
            when 'uniqueidentifier' then 'Guid' 
            when 'varbinary' then 'byte[]' 
            when 'varchar' then 'string' 
        end ColumnType 
    from sys.columns col join sys.types typ on col.system_type_id = typ.system_type_id 
    where object_id = object_id(@TableName) 
) t 
order by prop
open props
FETCH NEXT FROM props INTO @prop
WHILE @@FETCH_STATUS = 0
BEGIN
    print @prop
    FETCH NEXT FROM props INTO @prop
END
close props
DEALLOCATE props
PRINT 'End Class'

Java类生成

declare @TableName varchar(max) = 'Restaurants'
declare @Templete varchar(max) = ' 
     public @ColumnType @ColumnName ; // @ColumnDesc  
     public @ColumnType get@ColumnName()
     {
        return this.@ColumnName;
     }
     public void set@ColumnName(@ColumnType @ColumnName)
     {
        this.@ColumnName=@ColumnName;
     }

     '
declare @before varchar(max)='public class  @TableName  
{'
   
declare @after varchar(max)='
}'



declare @result varchar(max)

set @before =replace(@before,'@TableName',@TableName)

set @result=@before

select @result = @result 
+ replace(replace(replace(replace(replace(@Templete,'@ColumnType',ColumnType) ,'@ColumnName',ColumnName) ,'@ColumnDesc',ColumnDesc),'@ISPK',ISPK),'@max_length',max_length)

from  
(
    select 
    column_id,
    replace(col.name, ' ', '_') ColumnName,
    typ.name as sqltype,
    typ.max_length,
    is_identity,
    pkk.ISPK, 
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            when 'char' then 'String'
            when 'date' then 'DateTime'
            when 'datetime' then 'DateTime'
            when 'datetime2' then 'DateTime'
            when 'datetimeoffset' then 'DateTimeOffset'
            when 'decimal' then 'decimal'
            when 'float' then 'float'
            when 'image' then 'byte[]'
            when 'int' then 'int'
            when 'money' then 'decimal'
            when 'nchar' then 'char'
            when 'ntext' then 'string'
            when 'numeric' then 'decimal'
            when 'nvarchar' then 'String'
            when 'real' then 'double'
            when 'smalldatetime' then 'DateTime'
            when 'smallint' then 'short'
            when 'smallmoney' then 'decimal'
            when 'text' then 'String'
            when 'time' then 'TimeSpan'
            when 'timestamp' then 'DateTime'
            when 'tinyint' then 'byte'
            when 'uniqueidentifier' then 'Guid'
            when 'varbinary' then 'byte[]'
            when 'varchar' then 'string'
            else 'UNKNOWN_' + typ.name
        END + CASE WHEN col.is_nullable=1 AND typ.name NOT IN ('binary', 'varbinary', 'image', 'text', 'ntext', 'varchar', 'nvarchar', 'char', 'nchar') THEN '?' ELSE '' END ColumnType,
      isnull(colDesc.colDesc,'') AS ColumnDesc 
    from sys.columns col
        join sys.types typ on
            col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id
            left join
            (
                SELECT c.name  AS 'ColumnName', CASE WHEN dd.pk IS NULL THEN 'false' ELSE 'true' END ISPK           
                FROM        sys.columns c
                    JOIN    sys.tables  t   ON c.object_id = t.object_id    
                    LEFT JOIN (SELECT   K.COLUMN_NAME , C.CONSTRAINT_TYPE as pk  
                        FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS K 
                            LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS C
                        ON K.TABLE_NAME = C.TABLE_NAME
                            AND K.CONSTRAINT_NAME = C.CONSTRAINT_NAME
                            AND K.CONSTRAINT_CATALOG = C.CONSTRAINT_CATALOG
                            AND K.CONSTRAINT_SCHEMA = C.CONSTRAINT_SCHEMA            
                        WHERE K.TABLE_NAME = @TableName) as dd
                     ON dd.COLUMN_NAME = c.name
                 WHERE       t.name = @TableName       
            ) pkk  on ColumnName=col.name

    OUTER APPLY (
    SELECT TOP 1 CAST(value AS NVARCHAR(max)) AS colDesc
    FROM
       sys.extended_properties
    WHERE
       major_id = col.object_id
       AND
       minor_id = COLUMNPROPERTY(major_id, col.name, 'ColumnId')
    ) colDesc      
    where object_id = object_id(@TableName)

    ) t

    set @result=@result+@after

    select @result
    --print @result

如果你可以访问SQL Server 2016,你可以使用FOR JSON(包含INCLUDE_NULL_VALUES)选项从选择语句中获取JSON输出。复制输出,然后在Visual Studio中,粘贴special ->,粘贴JSON作为类。

算是预算上的解决方案,但可能会节省一些时间。

我只是想给感兴趣的人加上我自己的答案。 主要特点有:

It will automatically generate classes for all the tables in the entire schema. Just specify the schema name. It will add System.Data.Linq.Mapping attributes to the class and each property. Useful for anyone using Linq to SQL. declare @TableName sysname declare @Result varchar(max) declare @schema varchar(20) = 'dbo' DECLARE @Cursor CURSOR SET @Cursor = CURSOR FAST_FORWARD FOR SELECT DISTINCT tablename = rc1.TABLE_NAME FROM INFORMATION_SCHEMA.Tables rc1 where rc1.TABLE_SCHEMA = @schema OPEN @Cursor FETCH NEXT FROM @Cursor INTO @TableName WHILE (@@FETCH_STATUS = 0) BEGIN set @Result = '[Table(Name = "' + @schema + '.' + @TableName + '")] public class ' + Replace(@TableName, '$', '_') + ' {' select @Result = @Result + ' [Column' + PriKey +'] public ' + ColumnType + NullableSign + ' ' + ColumnName + ' { get; set; } ' from ( select replace(col.name, ' ', '_') ColumnName, col.column_id ColumnId, case typ.name when 'bigint' then 'long' when 'binary' then 'byte[]' when 'bit' then 'bool' when 'char' then 'string' when 'date' then 'DateTime' when 'datetime' then 'DateTime' when 'datetime2' then 'DateTime' when 'datetimeoffset' then 'DateTimeOffset' when 'decimal' then 'decimal' when 'float' then 'double' when 'image' then 'byte[]' when 'int' then 'int' when 'money' then 'decimal' when 'nchar' then 'string' when 'ntext' then 'string' when 'numeric' then 'decimal' when 'nvarchar' then 'string' when 'real' then 'float' when 'smalldatetime' then 'DateTime' when 'smallint' then 'short' when 'smallmoney' then 'decimal' when 'text' then 'string' when 'time' then 'TimeSpan' when 'timestamp' then 'long' when 'tinyint' then 'byte' when 'uniqueidentifier' then 'Guid' when 'varbinary' then 'byte[]' when 'varchar' then 'string' else 'UNKNOWN_' + typ.name end ColumnType, case when col.is_nullable = 1 and typ.name in ('bigint', 'bit', 'date', 'datetime', 'datetime2', 'datetimeoffset', 'decimal', 'float', 'int', 'money', 'numeric', 'real', 'smalldatetime', 'smallint', 'smallmoney', 'time', 'tinyint', 'uniqueidentifier') then '?' else '' end NullableSign, case when pk.CONSTRAINT_NAME is not null and ic.column_id is not null then '(IsPrimaryKey = true, IsDbGenerated = true)' when pk.CONSTRAINT_NAME is not null then '(IsPrimaryKey = true)' when ic.column_id is not null then '(IsDbGenerated = true)' else '' end PriKey from sys.columns col join sys.types typ on col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id left outer join sys.identity_columns ic on ic.column_id = col.column_id and col.object_id = ic.object_id left outer join ( SELECT K.TABLE_NAME , K.COLUMN_NAME , K.CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS C JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS K ON C.TABLE_NAME = K.TABLE_NAME AND C.CONSTRAINT_CATALOG = K.CONSTRAINT_CATALOG AND C.CONSTRAINT_SCHEMA = K.CONSTRAINT_SCHEMA AND C.CONSTRAINT_NAME = K.CONSTRAINT_NAME where C.CONSTRAINT_TYPE = 'PRIMARY KEY' ) pk on pk.COLUMN_NAME = col.name and pk.TABLE_NAME = @TableName where col.object_id = object_id(@schema + '.' + @TableName) ) t order by ColumnId set @Result = @Result + ' } ' print @Result FETCH NEXT FROM @Cursor INTO @TableName end CLOSE @Cursor DEALLOCATE @Cursor GO

增加了6-29-22:这是为EF Core (dotNet 6.0)生成模型的更新版本。

CREATE FUNCTION [dbo].[InitCap] ( @InputString varchar(4000) ) 
RETURNS VARCHAR(4000)
AS
BEGIN
    DECLARE @Index          INT
    DECLARE @Char           CHAR(1)
    DECLARE @PrevChar       CHAR(1)
    DECLARE @OutputString   VARCHAR(4000)

    SET @OutputString = @InputString
    SET @Index = 1

    WHILE @Index <= LEN(@InputString)
    BEGIN
        SET @Char     = SUBSTRING(@InputString, @Index, 1)
        SET @PrevChar = CASE WHEN @Index = 1 THEN ' '
                             ELSE SUBSTRING(@InputString, @Index - 1, 1)
                        END

        IF @PrevChar IN (' ', ';', ':', '!', '?', ',', '.', '_', '-', '/', '&', '''', '(')
            SET @OutputString = STUFF(@OutputString, @Index, 1, UPPER(@Char))

        SET @Index = @Index + 1
    END

    RETURN @OutputString
END
go


declare @TableName sysname
declare @Result varchar(max)
declare @schema varchar(20) = 'dbo'
DECLARE @Cursor CURSOR

SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT tablename = rc1.TABLE_NAME
FROM INFORMATION_SCHEMA.Tables rc1
where rc1.TABLE_SCHEMA = @schema

OPEN @Cursor FETCH NEXT FROM @Cursor INTO @TableName

WHILE (@@FETCH_STATUS = 0)
BEGIN
set @Result = '[Table("' + @TableName + '", Schema = "' + @schema + '")]
public class ' + Replace(@TableName, '$', '_') + '
{'

select @Result = @Result + '
    [Column("' + ColumnName + '"' + stringType + ')]
    public ' + ColumnType + NullableSign + ' ' + PropertyName + ' { get; set; }
'
from
(
    select 
        replace(col.name, ' ', '_') ColumnName,
        replace(replace([dbo].[InitCap](col.name), ' ', ''), '_', '') PropertyName,
        col.column_id ColumnId,
        case typ.name 
            when 'bigint' then 'long'
            when 'binary' then 'byte[]'
            when 'bit' then 'bool'
            when 'char' then 'string'
            when 'date' then 'DateTime'
            when 'datetime' then 'DateTime'
            when 'datetime2' then 'DateTime'
            when 'datetimeoffset' then 'DateTimeOffset'
            when 'decimal' then 'decimal'
            when 'float' then 'double'
            when 'image' then 'byte[]'
            when 'int' then 'int'
            when 'money' then 'decimal'
            when 'nchar' then 'string'
            when 'ntext' then 'string'
            when 'numeric' then 'decimal'
            when 'nvarchar' then 'string'
            when 'real' then 'float'
            when 'smalldatetime' then 'DateTime'
            when 'smallint' then 'short'
            when 'smallmoney' then 'decimal'
            when 'text' then 'string'
            when 'time' then 'TimeSpan'
            when 'timestamp' then 'long'
            when 'tinyint' then 'byte'
            when 'uniqueidentifier' then 'Guid'
            when 'varbinary' then 'byte[]'
            when 'varchar' then 'string'
            else 'UNKNOWN_' + typ.name
        end ColumnType,
        case 
            when col.is_nullable = 1
            then '?' 
            else '' 
        end NullableSign,
        case
            when typ.name in ('char', 'nchar', 'nvarchar', 'varchar')
            then ', TypeName = "' + typ.name + '(' + convert(varchar, col.max_length) + ')"'
            else ''
        end stringType
    from sys.columns col
    join sys.types typ on col.system_type_id = typ.system_type_id AND col.user_type_id = typ.user_type_id
    left outer join sys.identity_columns ic on ic.column_id = col.column_id and col.object_id = ic.object_id
    left outer join (
        SELECT  K.TABLE_NAME ,
            K.COLUMN_NAME ,
            K.CONSTRAINT_NAME
        FROM    INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS C
                JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS K ON C.TABLE_NAME = K.TABLE_NAME
                                                                 AND C.CONSTRAINT_CATALOG = K.CONSTRAINT_CATALOG
                                                                 AND C.CONSTRAINT_SCHEMA = K.CONSTRAINT_SCHEMA
                                                                 AND C.CONSTRAINT_NAME = K.CONSTRAINT_NAME
        where C.CONSTRAINT_TYPE = 'PRIMARY KEY'
    ) pk on pk.COLUMN_NAME = col.name and pk.TABLE_NAME = @TableName
    where col.object_id = object_id(@schema + '.' + @TableName)
) t
order by ColumnId

set @Result = @Result  + '
}

'

print @Result

FETCH NEXT FROM @Cursor INTO @TableName
end

CLOSE @Cursor DEALLOCATE @Cursor
GO

DROP FUNCTION [dbo].[InitCap]
GO