0
votes
1answer
146 views

Do certain string patterns affect query performance on a VARCHAR column?

I am a beginner on MySQL Administration and performance problems. Now this is confusing me. I have a VARCHAR column identity, the string in it is consisted of a Class type and an id, like note:123, ...
3
votes
1answer
449 views

Will one nvarchar column affect query performance?

I have one column that I recently converted to nvarchar(100) to store Asian characters. The other columns in this table, and the other tables in the same database, use varchar, int, bit and datetime. ...
4
votes
3answers
2k views

Should I add an arbitrary length limit to VARCHAR columns?

According to PostgreSQL's docs, there's no performance difference between VARCHAR, VARCHAR(n) and TEXT. Should I add an arbitrary length limit to a name or address column?
4
votes
2answers
534 views

varchar performance impact

This question has been asked before ( speed impact of using varchar in MSSQL 2008 ), but the answers are not detailed enough to my satisfaction. Admitedly this is not a current issue and mainly for ...
12
votes
3answers
1k views

Is there any point in undersizing VARCHAR columns?

Googling around there seems to be mixed reports whether the size of a VARCHAR2 column in Oracle impacts performance or not. I would like to give the question of VARCHAR size a little twist and hope ...
4
votes
4answers
436 views

How much will using a varchar(15) PK affect my tables performance?

I am parsing log file lines from a legacy, proprietary application into a nice easy to query DB. The log lines have no unique integer ID. They do have a UNIX timestamp as an 8 character hex string. ...