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https://issues.apache.org/jira/browse/TRAFODION-2968?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16589318#comment-16589318
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ASF GitHub Bot commented on TRAFODION-2968:
-------------------------------------------
Github user DaveBirdsall commented on a diff in the pull request:
https://github.com/apache/trafodion/pull/1698#discussion_r212092254
--- Diff:
docs/sql_reference/src/asciidoc/_chapters/sql_functions_and_expressions.adoc ---
@@ -11290,6 +11295,99 @@ ID
--- 1 row(s) selected.
```
+<<<
+[[uuid_function]]
+== UUID Function
+Returns a Universal Unique Identifier (UUID) generated according to RFC
4122.
+A UUID is designed as a number that is globally unique in space and time.
+Two calls to UUID() are expected to generate two different values, even if
+these calls are performed on two separate devices not connected to each
other.
+
+NOTE: But UUID() can only be used in SELECT list, or very simple
expressions to get a UUID.
--- End diff --
Do we prevent it from being used in the WHERE clause? If not, suggested
word-smith: "NOTE: UUID() behavior is non-deterministic. Therefore it is best
to use it only in SELECT lists. Using it in a WHERE clause, for example, may
result in non-deterministic predicate evaluation."
> update SQL manual for MySQL functions unix_timestamp, uuid, sleep etc
> ---------------------------------------------------------------------
>
> Key: TRAFODION-2968
> URL: https://issues.apache.org/jira/browse/TRAFODION-2968
> Project: Apache Trafodion
> Issue Type: Sub-task
> Reporter: liu ming
> Assignee: liu ming
> Priority: Major
>
> update the SQL manual to clearly state the non-deterministic fashion of newly
> added MySQL functions:
> uuid
> unix_timestamp
> sleep
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