PHP - advice for java HashMap alternative in php?
- by teutara
I know it is super noob and will be answered in no time, but I could not figure.. sorry for any inconvenience..
Here is the thing:
ID colA colB Length
1 seq1 seq11 1
2 seq1 seq11 11
3 seq3 seq33 21
4 seq3 seq33 14
I have a db with this kind of a table, has more than 10M rows. I want to loop though colA first, get the relevant colB value, and check if there are any other occurrences of the same value.
For example in colB (seq11) there are 2 occurrences of colA(seq1), this time I have to combine those and output the sum of the length. Similar to this:
ID colA colB Length
1 seq1 seq11 12
2 seq3 seq33 35
I am a bit java guy, but because my colleague has written everything in php and this will be just an adding, i need a php solution.
With java i would have used hashmap, so that I would have the colA data once and just increment the value of "Length Column"..
I know it is not a proper question, but..
Thank you in advance..
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EDIT
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I tried this query in order to group by occurences:
SELECT COUNT(*) SeqName FROM SeqTable GROUP BY SeqName HAVING COUNT(*)>0;
