On 1/28/19 8:10 AM, Durgamahesh Manne wrote:
On 1/28/19 6:20 AM, Durgamahesh Manne wrote:
> Hi
>
> below query is being executed for long time
>
> Select
> distinct ltrim(rtrim(ssnumber)), CL.iInsightClientId,
> ltrim(rtrim(TFA.client_account_key)) as vchAccountNumber,
> concat(TFA.first_name, ' ', TFA.last_name) as vchAccountName,
> concat('AP:TIAA', TFA.routing_number) as vchRepLabel,
> null as vchOpenDate, TFA.address1 as vchAccountTiteLine2,
> TFA.address2 as vchAccountTitleLine3,null as vchAccountType,
> TFA.address1 as vchPrimaryContact, 'TIAA-CREF' as Custodian,
> TFA.routing_number as vchCustodian_RepId, null as vchCustodianRepName,
> CONCAT ('TIAA-CREF:',ltrim(rtrim(client_account_key)),':',
> ltrim(rtrim(ssnumber))) as vchAccountKey,
> null as vchFeedsAccountType
> from accounts as TFA
> join client3 as CL on ltrim(rtrim(Cl.vchssnumber))=ltrim(rtrim(TFA.ssnumber))
> left join account3 as AC on
> ltrim(rtrim(AC."vchCustodianAccountNumber"))=ltrim(rtrim(TFA.client_account_key))
> where AC."iInsightAccountID" is null;
>
> query is being executed for long time even after i have created required
> indexes on columns of the tables
> please help for fast query execution
I bet this is what's causing your troubles:
on ltrim(rtrim(Cl.vchssnumber))=ltrim(rtrim(TFA.ssnumber))
The query optimizer probably can't use indexes on those tables.
Hi
why query optimizer can't use indexes on those columns of the tables
Because of the ltrim() functions. B-trees sort the data on the field values, and ltrim() changes that.
For example, these two strings are different, and therefore the b-tree puts them in different places in the tree.
snagglefrob
snagglefrob
Using lrtrim() makes them logically eqivalent, but not physically equivalent.
--
Angular momentum makes the world go 'round.
