database - Vendor will not create index because of data integrity -


i trying vendor create index on progress 10.2b database aid in migrating data said database, vendor reluctant create index, saying impact data integrity. there response below. truth/merit in being said?

there number of reasons not add indices main reason is, have outlined, progress selects index uses based on parameters in query. example if had code following:

find first record a= 1 , b = 2

as existing index stands find record using index ‘m’ , find record ‘x’

if add new index table there chance code decide use new index find record , return record ‘y’ instead.

sure creating indices core part of database, proper development practices require heaps of testing before applying index change product system. without testing, integrity of system cannot guaranteed.

so thoughts on are:

progress selects index uses based on parameters in query

isn't how database selects index? based on required columns/where clause, can decide appropriate index (if any) available.

if add new index table there chance code decide use new index find record , return record ‘y’ instead.

to me, sounds have programmed program rely on "grabbing first record out of database". if use index, sure, might order results differently if no order by has been specified. if case, poor programming.

i pretty agree you:

to me, sounds have programmed program rely on "grabbing first record out of database". if use index, sure, might order results differently if no order has been specified. if case, poor programming.

if wrote query correctly, index doesn't change result — speed. if left order , rely index has right order anyway, index cause problems.

however, emphasis this: bug query then.


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