How to get first rows

[craig322]

Is there a way other than SAMPLE to get rows from a table?

I am writing some error checking to verify that a table is populated using the ACTIVITYCOUNT feature. The tables I am running it against are rather large tables and if I use a statment like the following, it is taking a long time.

SELECT *
FROM large_table
SAMPLE 2;

.IF ACTIVITYCOUNT > 1 THEN .GOTO CONTPROC

Doing a count of the table always returns 1 row, so this doesn't work.

Does anyone have any ideas?

Thanks

Craig

 

[tdatgod]

Hi,
Activitycount works best with HAVING clause.

sel 1 from
mytable
having count(*) > 0;

.IF ACTIVITYCOUNT>0 THEN .GOTO CONTPROC

/* OOPS I guess I need to load this */
/* .OS out to SH and run my fastload script */

.os /home/user/loadmytable

.LABEL CONTPROC

 

[teradataman]

Or even:

SELECT 'ERROR - NO ROWS IN TAB1'
WHERE 0 = (SELECT COUNT(*) FROM TAB1)
;
.IF ACTIVITYCOUNT = 1 THEN .QUIT 16