16.10 - Improving Explain Text Readability - Teradata Database

To combine multiple ExplainText doc rows with the same query ID into one easily readable document, perform a SELECT request on the QryLogExplainDoc[V] view.

Example

sel queryid,explaintextdoc from qrylogexplaindocv where queryid=307188741814475132;

The result looks like the following partial output:

 *** Query completed. One row found. 2 columns returned.
 *** Total elapsed time was 1 second.

QueryID  ExplainTextDoc

  307188741814475132    1) First, we lock Test_DB.b12 for read on a reserved rowHash to      prevent global deadlock.    2) Next, we lock Test_DB.b3 for read on a reserved rowHash to      prevent global deadlock.    3) We lock Test_DB.b12 for read, and we lock Test_DB.b3 for      read.    4) We do an all-AMPs RETRIEVE step from Test_DB.b3 by way of an all-rows scan with a condition of ("NOT (Test_DB.b3.c2 IS NULL)") into Spool 2 (all_amps), which is redistributed by the hash code of (Test_DB.b3.c2) to all AMPs.  Then we do a SORT to order      Spool 2 by row hash.  The size of Spool 2 is estimated with low confidence to be 4 rows (68 bytes).  The estimated time for this step is 0.03 seconds.    5) We execute the following steps in parallel.... 

The memory allocated for the input is 32 MB. To see the memory setting, use the following:

cufconfig -o | grep MallocLimit

To add more memory, adjust the MallocLimit setting using cufconfig. For more information about cufconfig, see Utilities.