Hi,

Can somebody help me with Indexing. For e.g. I have a data sheet with

Airline Name (Col A), Sector Traveled (Col B) and Nett Payable (Col C) and then data in all rows.


Airline Name Sector Encoded Nett Pay
Kingfisher Delhi-Bhubaneswar 5633
Kingfisher Delhi-Bhubaneswar 5633
Kingfisher Delhi-Bhubaneswar 5633
Kingfisher Bhubaneswar-Delhi 5383
Kingfisher Bhubaneswar-Delhi 5383
Kingfisher Bhubaneswar-Delhi 5383
Indigo Airlines Bhubaneswar-Delhi 5057
Indigo Airlines Bhubaneswar-Delhi 5057
Indigo Airlines Delhi-Bhubaneswar 6073
Indigo Airlines Delhi-Bhubaneswar 9534
Kingfisher Kolkata-Raipur 5198
Jet Airways Raipur-Delhi 4068
Indigo Airlines Delhi-Bhubaneswar 6373
Kingfisher Bhubaneswar-Delhi 5383
Spice Jet Delhi-Gauhati 795
Kingfisher Delhi-Bhubaneswar 5633
Kingfisher Bhubaneswar-Delhi 5383
Jet Airways Delhi-Nagpur 840
Air India Delhi-Hyderabad 8745
Indigo Airlines Vadodara-Delhi 3413
Jet Airways Delhi-Vadodara 7149
Air India Nagpur-Delhi 4281
Spice Jet Delhi-Nagpur 4014
Jet Airways Delhi-Jodhpur 7059
Kingfisher Mumbai-Bangalore 4709
Jet Airways Bangalore-Mumbai 3359
Indigo Airlines Delhi-Ahmedabad-Delhi 8775
Air India Delhi-Raipur 6222
Indigo Airlines Delhi-Lucknow-Delhi 1680
Indigo Airlines Delhi-Bangalore 5705

How can I create a table which would pick common text (Airline Names) and summarize the Nett Pay??

Airline Name Nett Pay
Kingfisher 378041
Jet Airways 540244
Go Air 17746

Regards

for this query I'd want an index on airline name

I'd want to use the 'sum' clause
I'd want to use the 'group by' clause

id you want to understand the difference between indexing the airline name column then create the query without the indexes and use the explain prefix before and after creating the index and see what effect it has on the queries performance