So if cust_num is the 6 th index created on the table. Here is how you force the index while querying the database table :
select * from tranhist (6) where cust_num='AA25150'
Monday, February 22, 2010
Thursday, February 18, 2010
Excel Printing header on each line
Goto File -> Page Setup -> goto sheet tab -> In Print Titles section, Rows to repeat at top, enter the range of rows you would like to repeat : $1:$1
http://www.mrexcel.com/tip129.shtml
http://www.mrexcel.com/tip129.shtml
Wednesday, February 3, 2010
SQL Not in vs Join example
Obviously SQL join is more efficient than the not in clause. Here is an example of both.
Most inefficient Not in query :
select count(*)
from
wire_instr w
where
w.short_code
not in (select short_code
from nostro_accts)
Slightly better Not Exists query :
select count(*) from
wire_instr w
where not exists(
select 1
from nostro_accts n where
n.short_code=w.short_code)
Finally the Join query :
Join infact creates a new table which
select w.short_code as wshort,n.short_code as nshort from wire_instr w
left outer join
nostro_accts n
on n.short_code=w.short_code
where n.short_code=null
Enjoy
-Sunny
Most inefficient Not in query :
select count(*)
from
wire_instr w
where
w.short_code
not in (select short_code
from nostro_accts)
Slightly better Not Exists query :
select count(*) from
wire_instr w
where not exists(
select 1
from nostro_accts n where
n.short_code=w.short_code)
Finally the Join query :
Join infact creates a new table which
select w.short_code as wshort,n.short_code as nshort from wire_instr w
left outer join
nostro_accts n
on n.short_code=w.short_code
where n.short_code=null
Enjoy
-Sunny
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