Hi
There are two tables
Table 1 : final_account_bbs_tm
Table 2: apgvb_csp_cus_mapping
same column in both table global_account_num

I want records for table final_account_bbs_tm which does not exist in table
global_account_num for column global_account_num

Following is the query But it take so long long hours and finally too much load on mysql

Its EXPLAIN output

*************************** 1. row ***************************
id: 1
select_type: SIMPLE
table: fa
type: index
possible_keys: NULL
key: global_account_num
key_len: 303
ref: NULL
rows: 1272300
Extra: Using index
*************************** 2. row ***************************
id: 1
select_type: SIMPLE
table: asm
type: index
possible_keys: NULL
key: global_account_num_id1
key_len: 53
ref: NULL
rows: 1114569
Extra: Using where; Using index

Is there any other way to get same result in efficient way

a couple of items to point out in this query. First you are getting all 1272300 rows form you final account table. Why you would want that I can't even think of a reasonable answer, no one will ever read all of them. Next, you are selecting the same value twice, what good does that do for you? Do you really think any of two column pairs would not be identical when you joined on them? If you want to write a query, I think you should be specific and get just what you need. There are plenty of standards that folks have posted about for years, limit your select statement to just what you need, extra bytes cause for longer times, so if you know the value of a particular field, then do not select it. For instance your query has status = 'A', then you know the status is A and you do not have it in your select clause. You have a.col1 = b.col1, then you do not need both col1's in your select list, just one of them. The WHERE clause should have meaningful inputs to the query that will help limit what rows are returned to you, if not it will run longer.
Dave Nance

Thanks for your suggestion

My Requirement is
records that exist in fa.global_account_num but not in asm.global_account_num

output suppossed to be as follow
Yes we can avoid column asm.global_account_num but it will not make much
effect on performance

Is there any other way to get such results in much faster way

so why not write the SQL in that way?
Dave