>Hi, a have a doubt about the SELECT Clause in SQL Server with unique key indexes and the result of data, and why a difrent result with the same SELECT clause.
>
>I have 2 tables, the scrip follows:
>1º table
>

>SET ANSI_NULLS ON
>GO
>SET QUOTED_IDENTIFIER ON
>GO
>SET ANSI_PADDING ON
>GO
>
>IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[Teste1]') AND type in (N'U'))
>BEGIN
>CREATE TABLE [dbo].[Teste1](
>	[ID] [int] IDENTITY(1,1) NOT NULL,
>	[descricao] [char](10) COLLATE Latin1_General_CI_AS NOT NULL,
> CONSTRAINT [PK_Teste1_ID] PRIMARY KEY CLUSTERED 
>(
>	[ID] ASC
>) WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, 
> ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
>) ON [PRIMARY]
>END
>GO
>
>ALTER TABLE [dbo].[Teste1] DISABLE CHANGE_TRACKING 
>GO
>SET ANSI_PADDING OFF
>GO
>
>IF NOT EXISTS (SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID(N'[dbo].[Teste1]') AND name = N'IX_Teste1')
>CREATE UNIQUE NONCLUSTERED INDEX [IX_Teste1] ON [dbo].[Teste1] ([descricao] ASC) WITH (PAD_INDEX  = OFF, 
> STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, 
> ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
>GO
>

>
>2º table
>

>SET ANSI_NULLS ON
>GO
>SET QUOTED_IDENTIFIER ON
>GO
>SET ANSI_PADDING ON
>GO
>
>IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[Teste2]') AND type in (N'U'))
>BEGIN
>CREATE TABLE [dbo].[Teste2](
>	[ID] [int] IDENTITY(1,1) NOT NULL,
>	[descricao] [char](10) COLLATE Latin1_General_CI_AS NOT NULL,
>	[tipo] [char](10) COLLATE Latin1_General_CI_AS NOT NULL,
> CONSTRAINT [PK_Teste2] PRIMARY KEY CLUSTERED 
>(
>	[ID] ASC
>)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON,
> ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY],
> CONSTRAINT [IX_Descricao] UNIQUE NONCLUSTERED 
>(
>	[descricao] ASC
>)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, 
> ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
>) ON [PRIMARY]
>END
>GO
>
>ALTER TABLE [dbo].[Teste2] DISABLE CHANGE_TRACKING 
>GO
>SET ANSI_PADDING OFF
>GO
>
>IF NOT EXISTS (SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID(N'[dbo].[Teste2]') AND name = N'IX_Tipo')
>CREATE UNIQUE NONCLUSTERED INDEX [IX_Tipo] ON [dbo].[Teste2] 
>(
>	[tipo] ASC
>)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, 
>DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
>GO
>

>
>Now inserting 3 rows in each table:
>

>-- 1ª table
>insert into dbo.teste1 (descricao) values('C')
>insert into dbo.teste1 (descricao) values('B')
>insert into dbo.teste1 (descricao) values('A')
>
>-- 2ª table
>insert into dbo.teste2 (descricao, tipo) values('C', 'T1')
>insert into dbo.teste2 (descricao, tipo) values('B', 'T2')
>insert into dbo.teste2 (descricao, tipo) values('A', 'T3')
>

>
>Select in both tables:
>
>select * from dbo.Teste1
>select * from dbo.Teste2
>
>What I want to know is Why in the first table with the select clause the result was ordered bay the "descricao" column, and why in the second select the result of the same SELECT command was returned in order the data was inserted,(no order).
>
>Any ideia?

Yap,
SQL Server uses free space in database first and try to fill a whole page then add new space in DB.
That is why you should NEVER rely on "physical" order. There is no such thing in SQL Server. If you want your records ordered you must add ORDER BY clause in your queries.