I have:
Provide some context of how your icon could be used.
Include any example images so we know what the icon should look like.
Where is your use case and examples? The icon request issue template is not optional, so I've edited it back in. Please provide that information and we can consider the request.
Hello
I'm sorry,I didn't write an explanation for them, because it's a little difficult for them to explain!
Sql Query refers to the commands used to interact with the Microsoft SqlServer database.
These commands can include other commands called Sql SubQuery.
Example:
SELECT Id, Name,Family,
(SELECT Address
FROM PersonnelAddress
WHERE dbo.PersonnelAddress.PersonnelId = Personnel
) AS Address
FROM dbo.Personnel
These commands are called Sql Suery and the part that identifies the address is called Sql SubQuery.
@YousefGhafouri We know what SQL is 馃槃, what we needed was example images of how this could be represented. Search google for ideas if you can. Images can be pasted into GitHub comments.
An example can be found for sql query, but unfortunately there is no idea for sub query.

We avoid plaintext in icons in most cases. Also, the icon database-search exists already, and as long as you are in an SQL related page, just magnify will represent the idea just fine.
I have to agree with @JapanYoshi here. I think we're going to close this out. Feel free to come back with other examples if the icons he linked don't fit your use case.