整理 SQL Server 有用的语句，生成c# 实体，显示数据表的信息

1:数据表表生成C# Model实体类SQL语句

declare @TableName sysname = 'your table name' --指定表
 
select *, 'public ' + ColumnType + NullableSign + ' ' + ColumnName + ' { get; set; }' as AutoCode
from
(
    SELECT
        replace(col.name, ' ', '_') ColumnName,
        column_id ColumnId,
        prop.value ColName,
        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 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
    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 sys.extended_properties prop ON col.object_id = prop.major_id AND col.column_id = prop.minor_id
    where object_id = object_id(@TableName)
) t

2：查询所有表，字段，说明等详细信息

SELECT 
    表名       = case when a.colorder=1 then d.name else '' end,
    表说明     = case when a.colorder=1 then isnull(f.value,'') else '' end,
    字段序号   = a.colorder,
    字段名     = a.name,
    标识       = case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end,
    主键       = case when exists(SELECT 1 FROM sysobjects where xtype='PK' and parent_obj=a.id and name in (
                     SELECT name FROM sysindexes WHERE indid in( SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid))) then '√' else '' end,
    类型       = b.name,
    占用字节数 = a.length,
    长度       = COLUMNPROPERTY(a.id,a.name,'PRECISION'),
    小数位数   = isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0),
    允许空     = case when a.isnullable=1 then '√'else '' end,
    默认值     = isnull(e.text,''),
    字段说明   = isnull(g.[value],'')
FROM 
    syscolumns a
left join 
    systypes b 
on 
    a.xusertype=b.xusertype
inner join 
    sysobjects d 
on 
    a.id=d.id  and d.xtype='U' and  d.name<>'dtproperties'
left join 
    syscomments e 
on 
    a.cdefault=e.id
left join 
sys.extended_properties   g 
on 
    a.id=G.major_id and a.colid=g.minor_id  
left join
sys.extended_properties f
on 
    d.id=f.major_id and f.minor_id=0
--where 
--    d.name='Sys_User'
    
    --如果只查询指定表,加上此where条件，tablename是要查询的表名；去除where条件查询所有的表信息
order by 
    a.id,a.colorder