news:1121403112.160981.252840@g44g2000cwa.googlegroups.com...
> What are the major differences among data type VARCHAR, VARCHAR2, and
> CHAR?
>
> please advise. thanks!!
>

"Uri Dimant" wrote:

> Hi
> What is VARCHAR2 ?
>
> Using VARCHAR(n) , SQL Server will store one byte per chracter  so declared
> but unused chracters don't consume a storage
>
> As opposed using CHAR(n) it will store one byte per character declared even
> partially  unused
>
>
> <jrefact***@hotmail.com> wrote in message
> news:1121403112.160981.252840@g44g2000cwa.googlegroups.com...
> > What are the major differences among data type VARCHAR, VARCHAR2, and
> > CHAR?
> >
> > please advise. thanks!!
> >
>
>
>

"Uri Dimant" <u***@iscar.co.il> wrote in message
news:enngKrPiFHA.1412@TK2MSFTNGP09.phx.gbl...
> Hi
> What is VARCHAR2 ?
>
> Using VARCHAR(n) , SQL Server will store one byte per chracter  so
declared
> but unused chracters don't consume a storage
>
> As opposed using CHAR(n) it will store one byte per character declared
even
> partially  unused
>
>
> <jrefact***@hotmail.com> wrote in message
> news:1121403112.160981.252840@g44g2000cwa.googlegroups.com...
> > What are the major differences among data type VARCHAR, VARCHAR2, and
> > CHAR?
> >
> > please advise. thanks!!
> >
>
>

>
> It is also worth noting that each VarChar column has the additional overhead
> of a 2 byte header which stored bits related to the length of data. So
> VarChar(2) actually consumes 4 bytes of storage when full and 2 bytes when
> NULL. However, Char(2) consumes 2 bytes when full and 0 bytes when NULL.
> Therefore, Char is more storage efficient when storing fixed length strings
> like state codes and phone numbers, while VarChar is more efficient for
> variable lenth strings of fairly long length, such as address. Even a
> variable length string of 2 - 4 bytes might be better off as a Char to avoid
> the overhead of a VarChar.
>
> "Uri Dimant" <u***@iscar.co.il> wrote in message
> news:enngKrPiFHA.1412@TK2MSFTNGP09.phx.gbl...
> > Hi
> > What is VARCHAR2 ?
> >
> > Using VARCHAR(n) , SQL Server will store one byte per chracter  so
> declared
> > but unused chracters don't consume a storage
> >
> > As opposed using CHAR(n) it will store one byte per character declared
> even
> > partially  unused
> >
> >
> > <jrefact***@hotmail.com> wrote in message
> > news:1121403112.160981.252840@g44g2000cwa.googlegroups.com...
> > > What are the major differences among data type VARCHAR, VARCHAR2, and
> > > CHAR?
> > >
> > > please advise. thanks!!
> > >
> >
> >

"Gert-Jan Strik" <sorry@toomuchspamalready.nl> wrote in message
news:42D8173B.C25B085D@toomuchspamalready.nl...
> JT, this is (partially) incorrect.
>
> A char(2) column in SQL-Server 7.0 and later will always occupy 2 bytes
> plus 1 bit overhead (for the NULL-bitmap entry). So a char(80) column
> will occupy 80 bytes plus 1 bit overhead, regardless whether it is NULL
> or not.
>
> A varchar(2) column will occupy the actual data size (0 - 2 bytes) plus
> 2 bytes and 1 bit overhead (plus each row will use one extra byte simply
> because you are using one or more varying length data types). So this
> result in a minimum of 2 + 1 bit and a maximum of 4 bytes + 1 bit. A
> varchar(80) will therefore occupy between 2 and 82 bytes + 1 bit.
>
> So if you don't use trailing blanks, and you don't mind trimming
> trailing blanks, then from a space efficiency point of view one should
> not use Varchar for columns of 3 bytes or less and not use Char for
> columns with average data size less than the defined size - 3.
>
> Gert-Jan
>
>
>
> JT wrote:
>>
>> It is also worth noting that each VarChar column has the additional
>> overhead
>> of a 2 byte header which stored bits related to the length of data. So
>> VarChar(2) actually consumes 4 bytes of storage when full and 2 bytes
>> when
>> NULL. However, Char(2) consumes 2 bytes when full and 0 bytes when NULL.
>> Therefore, Char is more storage efficient when storing fixed length
>> strings
>> like state codes and phone numbers, while VarChar is more efficient for
>> variable lenth strings of fairly long length, such as address. Even a
>> variable length string of 2 - 4 bytes might be better off as a Char to
>> avoid
>> the overhead of a VarChar.
>>
>> "Uri Dimant" <u***@iscar.co.il> wrote in message
>> news:enngKrPiFHA.1412@TK2MSFTNGP09.phx.gbl...
>> > Hi
>> > What is VARCHAR2 ?
>> >
>> > Using VARCHAR(n) , SQL Server will store one byte per chracter  so
>> declared
>> > but unused chracters don't consume a storage
>> >
>> > As opposed using CHAR(n) it will store one byte per character declared
>> even
>> > partially  unused
>> >
>> >
>> > <jrefact***@hotmail.com> wrote in message
>> > news:1121403112.160981.252840@g44g2000cwa.googlegroups.com...
>> > > What are the major differences among data type VARCHAR, VARCHAR2, and
>> > > CHAR?
>> > >
>> > > please advise. thanks!!
>> > >
>> >
>> >