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@joey-qc
Created September 26, 2013 06:56
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A simple TSQL script to quickly generate c# POCO classes from SQL Server tables and views. You may tweak the output as needed. Not all datatypes are represented but this should save a bunch of boilerplate coding. USAGE: Run this query against the database of your choice. The script will loop through tables, views and their respective columns. Re…
declare @tableName varchar(200)
declare @columnName varchar(200)
declare @nullable varchar(50)
declare @datatype varchar(50)
declare @maxlen int
declare @sType varchar(50)
declare @sProperty varchar(200)
DECLARE table_cursor CURSOR FOR
SELECT TABLE_NAME
FROM [INFORMATION_SCHEMA].[TABLES]
OPEN table_cursor
FETCH NEXT FROM table_cursor
INTO @tableName
WHILE @@FETCH_STATUS = 0
BEGIN
PRINT 'public class ' + @tableName + ' {'
DECLARE column_cursor CURSOR FOR
SELECT COLUMN_NAME, IS_NULLABLE, DATA_TYPE, isnull(CHARACTER_MAXIMUM_LENGTH,'-1')
from [INFORMATION_SCHEMA].[COLUMNS]
WHERE [TABLE_NAME] = @tableName
order by [ORDINAL_POSITION]
OPEN column_cursor
FETCH NEXT FROM column_cursor INTO @columnName, @nullable, @datatype, @maxlen
WHILE @@FETCH_STATUS = 0
BEGIN
-- datatype
select @sType = case @datatype
when 'int' then 'Int32'
when 'decimal' then 'Decimal'
when 'money' then 'Decimal'
when 'char' then 'String'
when 'nchar' then 'String'
when 'varchar' then 'String'
when 'nvarchar' then 'String'
when 'uniqueidentifier' then 'Guid'
when 'datetime' then 'DateTime'
when 'bit' then 'Boolean'
else 'String'
END
If (@nullable = 'NO')
PRINT '[Required]'
if (@sType = 'String' and @maxLen <> '-1')
Print '[MaxLength(' + convert(varchar(4),@maxLen) + ')]'
SELECT @sProperty = 'public ' + @sType + ' ' + @columnName + ' { get; set;}'
PRINT @sProperty
print ''
FETCH NEXT FROM column_cursor INTO @columnName, @nullable, @datatype, @maxlen
END
CLOSE column_cursor
DEALLOCATE column_cursor
print '}'
print ''
FETCH NEXT FROM table_cursor
INTO @tableName
END
CLOSE table_cursor
DEALLOCATE table_cursor
@softgandhi
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softgandhi commented Mar 12, 2024

Thanks, I made my simplified version without using cursor, for single table:

declare @tableName varchar(200) = 'Compensation'

SELECT 'public class ' + @tableName + ' {'
UNION ALL
SELECT 
    '   '+ COLUMN_NAME + ' ' + case DATA_TYPE
        when 'int' then 'int'
        when 'decimal' then 'decimal'
        when 'money' then 'decimal'
        when 'char' then 'string'
        when 'nchar' then 'string'
        when 'smallint' then 'short'
        when 'varchar' then 'string'
        when 'nvarchar' then 'string'
        when 'uniqueidentifier' then 'Guid'
        when 'datetime' then 'DateTime'
        when 'bit' then 'bool'
        else 'string'
    END 
    + case when IS_NULLABLE = 'YES' and DATA_TYPE in ('int', 'money', 'smalldatetime', 'datetime', 'bit', 'float', 'decimal') then '?' else '' end
    + ' { get; set; }'
from [INFORMATION_SCHEMA].[COLUMNS] 
WHERE [TABLE_NAME] = @tableName
UNION ALL
SELECT '}'

@sun21170
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sun21170 commented May 10, 2024

This is a real gem for any developer in .Net. Thanks for this.
I have added a few lines of code to the original code, so that a developer can generate POCO for only one table or a comma-delimited list of table names. The new logic is marked by START and END comments in code below. To generate POCO for all tables, simply do not set the variable @tableNameForPOCO.

declare @tableName varchar(200)
declare @columnName varchar(200)
declare @nullable varchar(50)
declare @datatype varchar(50)
declare @maxlen int
declare @pos int

declare @Stype varchar(50)
declare @isnullable varchar(1)
declare @Sproperty varchar(200)

 ---START of new logic to limit to certain tables only---
DECLARE @tableNameForPOCO VARCHAR(200)--limits POCO class generation to only mentioned table(s)
--SET @tableNameForPOCO = 'Table1,Table2,Table3'--@tableNameForPOCO can be null to mean all tables 
                                                --or it can be set to a comma-delimited list of table names
                                                --there should be no space(s) before and after each comma in this list
DECLARE table_cursor CURSOR FOR
SELECT TABLE_NAME
FROM [INFORMATION_SCHEMA].[TABLES] WHERE  CASE
	WHEN ISNULL(@tableNameForPOCO, TABLE_NAME) LIKE ('%,' + TABLE_NAME + ',%') THEN 1
	WHEN ISNULL(@tableNameForPOCO, TABLE_NAME) LIKE (TABLE_NAME + ',%') THEN 1
	WHEN ISNULL(@tableNameForPOCO, TABLE_NAME) LIKE ('%,' + TABLE_NAME) THEN 1
	WHEN ISNULL(@tableNameForPOCO, TABLE_NAME) LIKE TABLE_NAME THEN 1
	ELSE 0
END = 1
 ---END of new logic to limit to certain tables only---

OPEN table_cursor

FETCH NEXT FROM table_cursor
INTO @tableName

WHILE @@FETCH_STATUS = 0
BEGIN

PRINT 'public class ' + @tableName + ' {'

DECLARE column_cursor CURSOR FOR 
SELECT COLUMN_NAME, IS_NULLABLE, DATA_TYPE, isnull(CHARACTER_MAXIMUM_LENGTH,'-1'), ORDINAL_POSITION
	, CASE WHEN (IS_NULLABLE = 'NO') THEN '' 
	ELSE 
		CASE WHEN (DATA_TYPE IN ('char','nchar','varchar','nvarchar')) THEN '' ELSE '?' END
	END

from [INFORMATION_SCHEMA].[COLUMNS] 
WHERE [TABLE_NAME] = @tableName
order by [ORDINAL_POSITION]

OPEN column_cursor
FETCH NEXT FROM column_cursor INTO @columnName, @nullable, @datatype, @maxlen, @pos, @isNullable

WHILE @@FETCH_STATUS = 0
BEGIN

-- datatype
select @sType = case @datatype
	when 'int' then 'int'
	when 'smallint' then 'short'
	when 'bigint' then 'long'
	when 'decimal' then 'Decimal'
	when 'money' then 'Decimal'
	when 'char' then 'string'
	when 'nchar' then 'string'
	when 'smallint' then 'short'
	when 'varchar' then 'string'
	when 'nvarchar' then 'string'
	when 'uniqueidentifier' then 'Guid'
	when 'datetime' then 'DateTime'
	when 'bit' then 'bool'
else 'string'
END

	If (@pos = 1)
		PRINT '	[Key]'
	If (@nullable = 'NO' AND @pos > 1)
		PRINT '	[Required]'
	if (@sType = 'string' and @maxLen <> '-1')
		PRINT '	[MaxLength(' +  convert(varchar(4),@maxLen) + ')]'
	if (@sType = 'datetime')
		PRINT '	[Column(TypeName = "datetime")]'
	SELECT @sProperty = '	public ' + @sType + @isNullable + ' ' + @columnName + ' { get; set; }'
	PRINT @sProperty

	--print ''
	FETCH NEXT FROM column_cursor INTO @columnName, @nullable, @datatype, @maxlen, @pos, @isNullable
END
CLOSE column_cursor
DEALLOCATE column_cursor

print '}'
print ''
FETCH NEXT FROM table_cursor 
INTO @tableName
END
CLOSE table_cursor
DEALLOCATE table_cursor

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