Explanation
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| | 1) | First, we lock a distinct DEV_TAMPON."pseudo table" for read on a RowHash to prevent global deadlock for DEV_TAMPON.table_two.
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| | 2) | Next, we lock a distinct DEV_TAMPON."pseudo table" for read on a RowHash to prevent global deadlock for DEV_TAMPON.A.
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| | 3) | We lock DEV_TAMPON.table_two for read, and we lock DEV_TAMPON.A for read.
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| | 4) | We do an all-AMPs RETRIEVE step from DEV_TAMPON.table_two by way of an all-rows scan with no residual conditions into Spool 3
(all_amps), which is redistributed by hash code to all AMPs. Then we do a SORT to order Spool 3 by the sort key in spool field1 eliminating
duplicate rows. The size of Spool 3 is estimated with low confidence to be 2 rows. The estimated time for this step is 0.03 seconds.
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| | 5) | We do an all-AMPs RETRIEVE step from Spool 3 (Last Use) by way of an all-rows scan into Spool 2 (all_amps), which is duplicated on
all AMPs. The size of Spool 2 is estimated with no confidence to be 4 rows.
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| | 6) | We do an all-AMPs JOIN step from DEV_TAMPON.A by way of an all-rows scan with no residual conditions, which is joined to Spool 2
(Last Use). DEV_TAMPON.A and Spool 2 are joined using an exclusion product join, with a join condition of ("DEV_TAMPON.A.JOB_CODE =
JOB_CODE"). The result goes into Spool 1 (group_amps), which is built locally on the AMPs. The size of Spool 1 is estimated with index
join confidence to be 2 rows. The estimated time for this step is 0.03 seconds.
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| | 7) | Finally, we send out an END TRANSACTION step to all AMPs involved in processing the request.
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| | -> | The contents of Spool 1 are sent back to the user as the result of statement 1. The total estimated time is 0.06 seconds.
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