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#1 (**permalink**) 02-27-2008, 06:30 AM

hi ,

i have some simple doubt in DB2
1. can we disable or enable an INDEX.
2. can we drop a column from a table .
3. can we change the datatype of a column i.e say from varchar to
integer

Please help me update my knowledge.

thanks
bikash

#2 (**permalink**) 02-27-2008, 06:30 AM

bikkaran@in.ibm.com wrote:

> hi ,
>
> i have some simple doubt in DB2
> 1. can we disable or enable an INDEX.

What do you have in mind with disable/enable? Should the index not be used
during queries or not being maintained during DML statements?

> 2. can we drop a column from a table .

Not yet. But the Control Center provides a way to do that.

> 3. can we change the datatype of a column i.e say from varchar to
> integer

No.

--
Knut Stolze
DB2 Information Integration Development
IBM Germany

#3 (**permalink**) 02-27-2008, 06:30 AM

bikkaran@in.ibm.com wrote:
> hi ,
>
> i have some simple doubt in DB2
> 1. can we disable or enable an INDEX.
DROP INDEX....
> 2. can we drop a column from a table .
In DB2 V8 for zOS yes. In DB2 for LUW this will be supported in Viper,
today (V8.2) there is GUI driven support in the control center.
> 3. can we change the datatype of a column i.e say from varchar to
> integer
In DB2 for LUW you can INCREASE the length of a VARCHAR column.
In Viper you will be able to do any alter which cannot cause loss of data.
VARCHAR->INTEGER: No
INTEGER->VARCHAR: I think yes in Viper.

Cheers
Serge

--
Serge Rielau
DB2 Solutions Development
IBM Toronto Lab

#4 (**permalink**) 02-27-2008, 06:31 AM

Serge Rielau wrote:
> bikkaran@in.ibm.com wrote:
>> hi ,
>>
>> i have some simple doubt in DB2
>> 1. can we disable or enable an INDEX.
> DROP INDEX....
>> 2. can we drop a column from a table .
> In DB2 V8 for zOS yes. In DB2 for LUW this will be supported in Viper,
> today (V8.2) there is GUI driven support in the control center.
>> 3. can we change the datatype of a column i.e say from varchar to
>> integer
> In DB2 for LUW you can INCREASE the length of a VARCHAR column.
> In Viper you will be able to do any alter which cannot cause loss of
> data.
> VARCHAR->INTEGER: No
> INTEGER->VARCHAR: I think yes in Viper.
>
> Cheers
> Serge
>
Just be careful on the GUI driven option as I believe the underlying
task is to drop and recreate the table?

Bob

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