Solved

maximum size of VARCHAR2()

Posted on 2006-07-15
7
23,080 Views
Last Modified: 2008-06-04
What is the maximum size of VARCHAR2(),
Is it 3000?
If yes,
If I create table with VARCHAR2(3000) is it wasting the memory or it will cover only what space I used?


For example,

         Create table x (name VARCHAR2(3000));

 and

          Insert into x (name) values (‘SQL’);

I used only 3, Does this waste 2997 or not?
0
Comment
Question by:javamate06
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
7 Comments
 
LVL 37

Accepted Solution

by:
Harisha M G earned 30 total points
ID: 17116765
Hi javamate06, in which database ? Oracle ?

If you use VARCHAR2, it won't waste any space.

http://www.ss64.com/orasyntax/datatypes.html


---
Harish
0
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 17116777
In Oracle: 4000
In MSSQL (2000): 8000
in MSSQL (2005):  MAX = 2GB

In all the databases, there is NO waste of space.
0
 
LVL 3

Expert Comment

by:cdemir
ID: 17116784
in Oracle;

>> What is the maximum size of VARCHAR2(),
varchar2(4000)

>> I used only 3, Does this waste 2997 or not?
No. Allowing extra space in a VARCHAR column is usually harmless — after all, the definition doesn’t affect the storage — but it does affect sorts.
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:javamate06
ID: 17116805
thanks mgh_mgharish

You said "If you use VARCHAR2, it won't waste any space.". So, is there a type like VARCHAR2 wasiting spaces by initializing the size?
0
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 17116807
yes, using CHAR(4000) will allocate each time 4000 characters
0
 
LVL 37

Expert Comment

by:Harisha M G
ID: 17116822
angel is correct..

>> but it does affect sorts.
Performence can be increased slightly by creating index on that column
0
 
LVL 50

Expert Comment

by:Lowfatspread
ID: 17116880
Hi javamate06,
performance is also affected by having to store the length of the data with the column...
but that's not usually a concern if your storing a lot of data...

a general rules of thumb from db2/udb
if its less than 30 bytes define it as char to its maximum value
if it generally varies by less than 10-20 bytes use char


hth
 


Cheers!
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Documenting Data flow 4 55
Is Dropbox the only way to upload large files? 3 51
Shrink multiple databases at once 4 55
Need to trim my database size 9 24
Entity Framework is a powerful tool to help you interact with the DataBase but still doesn't help much when we have a Stored Procedure that returns more than one resultset. The solution takes some of out-of-the-box thinking; read on!
Never store passwords in plain text or just their hash: it seems a no-brainier, but there are still plenty of people doing that. I present the why and how on this subject, offering my own real life solution that you can implement right away, bringin…
Video by: Steve
Using examples as well as descriptions, step through each of the common simple join types, explaining differences in syntax, differences in expected outputs and showing how the queries run along with the actual outputs based upon a simple set of dem…
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

733 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question