"If you know solution please answer otherwise keep quite ! I know i need to study PL/SQL. Nobody is here to listen your free suggestion!". hahah.

@Philᵀᴹ Was that posted on DBA.SE? I'm curious to see if there's any way I could quietly express my appreciation of that kind of attitude

@AndriyM The OP deleted the question. dba.stackexchange.com/questions/239084/…

@Philᵀᴹ Good for them. It was a cross-post anyway.

I shall continue to offer my free suggestions :-)

Another curious thing is that they had deleted/undeleted their DBA.SE question several times, some of those in quick succession too

I wonder if that's a technique of some sorts to achieve something

@AndriyM Sometimes people do that because it doesn't look like deletion accomplished the desired effect - after all, they can still see the post.

No way to know what happened in this specific instance though

Could well be the case, the OP is still relatively new to the network.