Hi,
I am in the process writing scripts for CHAR/VARCHAR to
NCHAR/NVARCHAR conversion..Infact i have completed
it..When I run these scripts against DB is verly
slow..This is happening when i run convert scripts
eaxctly..Even select name from sysobjects doesn't return
values..There are heavy IO is going on the DB..what are
the areas i should concentrate the to improve performance..
Basically I have written cursor whic executes one by one
the alter scripts..
Sridhar...
Changing a CHAR to VARCHAR will most likely involve each row being affected
and hence all the I/O. If you are altering more than one column per table
you might get better performance by creating a second table with the changed
columns and Inserting all the rows into it. Drop the original, rename the
new to the old and add the appropriate indexes, RI etc.. Just make sure you
have good backups first.
Andrew J. Kelly SQL MVP
<anonymous@.discussions.microsoft.com> wrote in message
news:297601c47e07$62bd4ae0$a501280a@.phx.gbl...
> Hi,
> I am in the process writing scripts for CHAR/VARCHAR to
> NCHAR/NVARCHAR conversion..Infact i have completed
> it..When I run these scripts against DB is verly
> slow..This is happening when i run convert scripts
> eaxctly..Even select name from sysobjects doesn't return
> values..There are heavy IO is going on the DB..what are
> the areas i should concentrate the to improve performance..
>
> Basically I have written cursor whic executes one by one
> the alter scripts..
>
> Sridhar...
>
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