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Message Posted: Thu, 21 Mar 2002 @ 21:36:34 GMT


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Subj:		Re: Sample query

From:		Anwar P

If it is any consolation, casting TIME/TIMESTAMP to VARCHAR/CHAR should get you going. But you will be forced to spell out your columns. Please see sample below.

Anwar.

create table foo
(c int, t timestamp);

 *** Table has been created.

explain select * from foo sample 10;

`Explanation --------------------------------------------------`
	`1)`	`First, we lock a distinct TEST1."pseudo table" for read on a RowHash to prevent global deadlock for TEST1.foo.`
	`2)`	`Next, we lock TEST1.foo for read.`
	`3)`	`We do an all-AMPs RETRIEVE step from TEST1.foo by way of an all-rows scan with no residual conditions into Spool 2, which is built locally on the AMPs. The size of Spool 2 is estimated with low confidence to be 60 rows. The estimated time for this step is 0.15 seconds.`
	`4)`	`We do an all-AMPs SAMPLING step from Spool 2 (Last Use) by way of an all-rows scan into Spool 1, which is built locally on the AMPs. Samples are specified as number of rows..`
	`5)`	`Finally, we send out an END TRANSACTION step to all AMPs involved in processing the request.`
	`->`	`The contents of Spool 1 are sent back to the user as the result of statement 1.`

explain select c, cast(t as varchar(30)) from foo sample 10;

`Explanation --------------------------------------------------`
	`1)`	`First, we lock a distinct TEST1."pseudo table" for read on a RowHash to prevent global deadlock for TEST1.foo.`
	`2)`	`Next, we lock TEST1.foo for read.`
	`3)`	`We do an all-AMPs SAMPLING step from TEST1.foo by way of an all-rows scan with no residual conditions into Spool 1, which is built locally on the AMPs. Samples are specified as number of rows..`
	`4)`	`Finally, we send out an END TRANSACTION step to all AMPs involved in processing the request.`
	`->`	`The contents of Spool 1 are sent back to the user as the result of statement 1.`

 BTEQ -- Enter your DBC/SQL request or BTEQ command:


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