Matthew Jacobs has posted comments on this change. Change subject: IMPALA-4738: STDDEV_SAMP should return NULL for single record input ......................................................................
Patch Set 3: Code-Review+2 (2 comments) Thanks! Please let John know that the existing doc needs to be updated. http://gerrit.cloudera.org:8080/#/c/5800/3//COMMIT_MSG Commit Message: PS3, Line 9: In calculating the STDDEV_SAMP/VARIANCE of N rows a divion by N-1 rows is involved. : Hence STDDEV_SAMP/VARIANCE for a single row involves a division by 0. This change : returns a NULL instead of a 0 when calculating STDDEV_SAMP/VARIANCE for a single row. : STDDEV_POP/VARIANCE_POP for single row will still return a 0 since this does not involve a division : by 0. nit wrap at 80 chars Line 14: please mention this matches postgres behavior -- To view, visit http://gerrit.cloudera.org:8080/5800 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Ide8af752cd8a2e554a2cd5a1ec948967a80de1fe Gerrit-PatchSet: 3 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: anujphadke <[email protected]> Gerrit-Reviewer: Matthew Jacobs <[email protected]> Gerrit-Reviewer: anujphadke <[email protected]> Gerrit-HasComments: Yes
