T-SQL user guide

==================== Calcul d’ un max d’ un champs ====================
Unicode = 2 caractères
SQL Server also has a DATALENGTH() function.  This function can be used on all data types
(Text, NText or Image data types) in your table.

SELECT a020, DATALENGTH(a020)
FROM dbo.notices


Ordre décroissant :
SELECT a020, DATALENGTH(a020)
FROM dbo.notices
ORDER BY 2 DESC

le maximun :
SELECT TOP 1 a020, DATALENGTH(a020)
FROM dbo.notices
ORDER BY 2 DESC

=================================================================
Merge de tables SQL / As for performance, so long as the id field(s) in tablea (the big table)
are indexed, you should be fine.
===================================================

begin tran;
delete from Source1 where exists (select 1 from Depouillement where Depouillement.isn=Source1.isn);
insert into Depouillement select * from source1;
commit tran;

option 2:
begin tran;
delete from tablea where exists (select 1 from tableb where tablea.id=tableb.id);
insert into tablea select * from tableb;
commit tran;

option 3:
begin tran;
delete from tableb where exists (select 1 from tablea where tablea.id=tableb.id);
insert into tablea select * from tableb;
commit tran;

============== Incrémenter un champ type ID =================

DECLARE @id int
set @id = 0
UPDATE A230 SET id = @id, @id = @id + 1

======================= timestamp binary data sql =====

select convert(int, timestamp) as version from products
select convert(bigint, timestamp) as version from products

===================== How to empty Log files ===============

backup log [wahda] with truncate_only
go
DBCC SHRINKDATABASE ([wahda], 10, TRUNCATEONLY)
go

SECURISER BASE SQL + ACCES INETPUB (Application Web)
=============================================

if not exists (select * from master.dbo.syslogins where loginname = N'WidgetStoreDAL')
exec sp_addlogin N'WidgetStoreDAL', N'password', N'WidgetStore', N'us_english'
GO
if not exists (select * from dbo.sysusers where name = N'WidgetStoreDAL')
EXEC sp_grantdbaccess N'WidgetStoreDAL', N'WidgetStoreDAL'
GO

exec sp_addrolemember N'db_denydatareader', N'WidgetStoreDAL'
GO

exec sp_addrolemember N'db_denydatawriter', N'WidgetStoreDAL'
GO

=======================================================================
if not exists (select * from master.dbo.syslogins where loginname = N'DOTNET2010\ASPNET')
exec sp_grantlogin N'DOTNET2010\ASPNET'
exec sp_defaultdb N'DOTNET2010\ASPNET', N'WidgetStore'
exec sp_defaultlanguage N'DOTNET2010\ASPNET', N'us_english'
GO

if not exists (select * from dbo.sysusers where name = N'DOTNET2010\ASPNET')
EXEC sp_grantdbaccess N'DOTNET2010\ASPNET', N'DOTNET2010\ASPNET'
GO

exec sp_addrolemember N'db_denydatareader', N'DOTNET2010\ASPNET'
GO

exec sp_addrolemember N'db_denydatawriter', N'DOTNET2010\ASPNET'
GO