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Message
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| vijsam |
 Posted: Thu Feb 02, 2012 7:16 am Post subject: count related function in esql |
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Apprentice
Joined: 01 Jun 2011
Posts: 46
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Hello All,
I need to count how many times a particular character in a string is repeatating,
example want to calculate the number of commas in value like:sam,ram,mbm. need your asisatnce. |
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| Vitor |
| Posted: Thu Feb 02, 2012 7:26 am Post subject: Re: count related function in esql |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| vijsam wrote: |
| I need to count how many times a particular character in a string is repeatating, |
AFAIK there's no supplied function that does this in ESQL. It would be a trivial task to write your own (I came up with 2 possible methods in 1 sip of coffee).
I'll leave others to comment on the possibilities Java offers. I would imagine there's some kind of tokenising facility & you could count the tokens but I imagine a lot of things that turn out not to be true.
_________________
Honesty is the best policy.
Insanity is the best defence. |
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| kash3338 |
| Posted: Thu Feb 02, 2012 7:26 am Post subject: Re: count related function in esql |
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Shaman
Joined: 08 Feb 2009
Posts: 709
Location: Chennai, India
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| vijsam wrote: |
I need to count how many times a particular character in a string is repeatating,
example want to calculate the number of commas in value like:sam,ram,mbm. need your asisatnce. |
You can write a simple function for that in ESQL with a IN parameter as the character to be checked and OUT parameter as the count. |
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| lancelotlinc |
| Posted: Thu Feb 02, 2012 7:28 am Post subject: |
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Jedi Knight
Joined: 22 Mar 2010
Posts: 4941
Location: Bloomington, IL USA
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| mqsiuser |
| Posted: Thu Feb 02, 2012 7:41 am Post subject: |
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Yatiri
Joined: 15 Apr 2008
Posts: 637
Location: Germany
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| Code: |
CREATE FUNCTION countCharInChar(IN char1 CHAR, IN char2 CHAR) RETURNS INT
-- Returns the number of occurences of char1 in char2
-- E.g.: ('A', 'ABCDABCDABCD') --> 3
-- ('ABC', 'ABCDABCD') --> 2
-- ...
BEGIN
DECLARE count INT 0;
IF char1 IS NOT NULL AND char2 IS NOT NULL THEN
DECLARE position1 INT POSITION( char1 IN char2 REPEAT count+1 );
WHILE position1 <> 0 DO
SET count = count + 1;
SET position1 = POSITION( char1 IN char2 REPEAT count+1 );
END WHILE;
END IF;
RETURN count;
END; |
Simple things should also be done with care !
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Just use REFERENCEs |
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| adubya |
| Posted: Thu Feb 02, 2012 7:53 am Post subject: |
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Partisan
Joined: 25 Aug 2011
Posts: 377
Location: GU12, UK
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SET tmpString = REPLACE ( originString, ',' );
SET count = LENGTH ( originString) - LENGTH (tmpString);
or
SET count = LENGTH ( originString) - LENGTH ( REPLACE ( originString, ',' ) );
There are many ways to skin a cat.
Method #54: Sandblasting. |
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| mqsiuser |
| Posted: Thu Feb 02, 2012 8:32 am Post subject: |
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Yatiri
Joined: 15 Apr 2008
Posts: 637
Location: Germany
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| adubya wrote: |
| There are many ways to skin a cat. |
We are searching for the fastest (and most appropriate) approach.
Your approach looks elegant, but manipulating strings (changing a string) can be expensive in memory-space and processing-time. That's why Java has something called a StringBuffer/Builder. The wiki-page says: "In order to insert or remove characters at arbitrary positions, whole sections of arrays must be moved". It works similar with C/ESQL... there actually is a best practice for performance in Broker, which is "try to avoid string manipulation".
Looping with increasing the pos-counter might also get slow (for large strings), I must admit.
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| vijsam |
| Posted: Fri Feb 03, 2012 12:49 am Post subject: |
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Apprentice
Joined: 01 Jun 2011
Posts: 46
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Thanku all for the valuable inputs  |
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| Vitor |
| Posted: Fri Feb 03, 2012 6:01 am Post subject: |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| lancelotlinc wrote: |
Or  Java Compute Node. |
For the record, I deliberately said Java. Perhaps even called as a function from ESQL if you don't want to go JCN.
Is there some kind of tokenizing thing? Not as an answer to the OP but just to see if I was imagining that & need to adjust my medication. Again.
_________________
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Insanity is the best defence. |
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| kimbert |
| Posted: Fri Feb 03, 2012 6:07 am Post subject: |
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Jedi Council
Joined: 29 Jul 2003
Posts: 5543
Location: Southampton
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Vitor: Java cannot tokenize stuff. Ever. Please adjust your medication.  |
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| mqjeff |
| Posted: Fri Feb 03, 2012 6:33 am Post subject: |
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Grand Master
Joined: 25 Jun 2008
Posts: 17447
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| kimbert wrote: |
| Vitor: Java cannot tokenize stuff. Ever. Please adjust your medication. |
No, no. Vitor needs *more* Java...  |
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| Vitor |
| Posted: Fri Feb 03, 2012 6:51 am Post subject: |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| kimbert wrote: |
| Vitor: Java cannot tokenize stuff. Ever. Please adjust your medication. |
Just when I think I'm getting somewhere.... 
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| mqjeff |
| Posted: Fri Feb 03, 2012 6:55 am Post subject: |
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Grand Master
Joined: 25 Jun 2008
Posts: 17447
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