Char or Varchar ?

Henry

Delphi Developer

Char or Varchar ?

2005-12-01 04:51:27 PM
delphi103
What is the difference between Char and Varchar ?
Is there any advantage to use varchar instead char ?
Thank you.

Martijn Tonies

Delphi Developer

2005-12-01 05:35:28 PM

Re:Char or Varchar ?

Quote

What is the difference between Char and Varchar ?
CHAR is a logical format that pads spaces to the end

until it fills up the declared length.
So storing "yes" in a CHAR(10) column will end up
like this:
"yes "
when doing a SELECT.

Quote

Is there any advantage to use varchar instead char ?
VARCHAR doesn't pad spaces, so if you store

"yes", it will return "yes".
Varchar takes 2 bytes (or so) more space cause it has
to save the actual length of the data. So if you do a
boolean-like column with possible values Y, N ->then
use CHAR(1) (no spaces either way).
For the rest, I would use VARCHAR.
--
Martijn Tonies
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Don Bowen

Delphi Developer

2005-12-01 08:33:24 PM

Re:Char or Varchar ?

"Henry" <XXXX@XXXXX.COM>writes:

Quote

What is the difference between Char and Varchar ?
Is there any advantage to use varchar instead char ?

Thank you.

As I understand, varchar will store a variable length of

characters where char will store a set amount.
varchar(40) = 'Fred' = <stores 4 characters in file>
char(40) = 'Fred' = <stores 40 characters in file>
is this correct?