Code explanation needed

Can someone put in understandable description what this code is doing?

select /*+ no_parallel_index(t,"IDX_LEDGERTEMP_CONNID") dbms_stats cursor_sharing_exact use_weak_name_resl dynamic_sampling(0) no_monitoring no_expand index(t,"IDX_LEDGERTEMP_CONNID") */ count(*) as nrw,count(distinct sys_op_lbid(124888,'L',t.rowid)) as nlb,count(distinct "CONN_ID") as ndk,sys_op_countchg(substrb(t.rowid,1,15),1) as clf from "NIS1"."LEDGERENTRY_TEMP" t where "CONN_ID" is not null
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

It's doing an analyze of your table to gather index information.

Most of those hints aren't usable by developers in their applications.
If you're looking for a more detailed explanation, you'd have to go to oracle to get a complete and accurate description of each step...

but in general, what it's doing is

scanning your table using an index in one session (no-parallel means don't multi-thread it)
cursor_sharing_exact tells the optimizer to NOT replace constants with bind variables, but to use the sql statement "as-is".

it's reading every row of data, rather than randomly sampling some percentage. and counting the total number of rows and distinct values and by parsing the rowid is gathering the clustering and leaf block information.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
That is an oracle internal script used to gather stats.
Yes, I guess I wasn't specific enough  the "analyze" I was referring to was initiated by a call to the dbms_stats package.

It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Oracle Database

From novice to tech pro — start learning today.