mdayakar commented on code in PR #4965:
URL: https://github.com/apache/hive/pull/4965#discussion_r1444240588
##########
hplsql/src/main/java/org/apache/hive/hplsql/functions/FunctionString.java:
##########
@@ -33,38 +33,30 @@ public FunctionString(Exec e, QueryExecutor queryExecutor) {
public void register(BuiltinFunctions f) {
f.map.put("CONCAT", this::concat);
f.map.put("CHAR", this::char_);
- f.map.put("INSTR", this::instr);
f.map.put("LEN", this::len);
- f.map.put("LENGTH", this::length);
- f.map.put("LOWER", this::lower);
- f.map.put("REPLACE", this::replace);
- f.map.put("SUBSTR", this::substr);
- f.map.put("SUBSTRING", this::substr);
f.map.put("TO_CHAR", this::toChar);
f.map.put("UPPER", this::upper);
-
- f.specMap.put("SUBSTRING", this::substring);
- f.specMap.put("TRIM", this::trim);
Review Comment:
> I suppose the reason for removing SUBSTRING, TRIM and a few other
functions is that these are builtin functions in Hive.
Yes Aman.
> so is HPL/SQL going to forward the function call to HS2 ?
Yes, in this case it will just forward the function call to HS2
> One thing we should verify is if the HPL/SQL behavior of these functions
is the same as what the Hive built-in function does or is there any small
difference.
Yes Aman, if there is any behaviour change or some extra feature for any
function then that code is not removed. Actually for SUBSTRING also later found
that it supports another functionality 'SUBSTRING(string FROM start_pos [FOR
substring_len])' which is not present in HS2 so added back the SUBSTRING
function code. Similar for CONCAT (if any param is NULL then HS2 returns NULL
as output where as HPLSQL function ignores NULLs and concats other non-null
strings) so this function also not removed.
> I am curious why these were implemented in HPL/SQL in the first place
since these are SQL standard functions.
As per my understanding HPLSQL initially provided as a separate entity (not
part of Hive) and later it got merged as a part of Hive. When it was a separate
entity, it can be used not only with Hive also can be with any other Databases
like DB2, MySQL,... so they might provided implementation for all these
functions now its part of Hive release so I assumed it can be used only with
Hive so I removed the functions implementation which are already supported in
Hive.
> Was there additional precondition checks being done or any other variants
that HPL/SQL supported that Hive did not ?
The code is already present and I could see there are some precondition
checks present.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: gitbox-unsubscr...@hive.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: gitbox-unsubscr...@hive.apache.org
For additional commands, e-mail: gitbox-h...@hive.apache.org
