feat: add pg create alter table expr translator

[WenyXu]

I hereby agree to the terms of the GreptimeDB CLA

What's changed and what's your intention?

1. Add alter table expr translator
2. Add create table expr translator

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

Refer to a related PR or issue link (optional)

#3174

waits for #3203

[zhongzc]

There is a translator called greptime. Is it the mysql protocol?

[WenyXu]

There is a translator called greptime. Is it the mysql protocol?

I guess it is called a dialect more precisely, instead of a protocol. No matter what we use which protocol in greptime, it always supports the show create table, and desc table statements.

[zhongzc]

I guess it is called a dialect more precisely, instead of a protocol. No matter what we use which protocol in greptime, it always supports the show create table, and desc table statements.

I noticed that the translator mod has two submods, one is greptime and the other is postgres. Many of their codes are similar, so I am curious whether there is a dialect of greptime or just MySQL.

[WenyXu]

I noticed that the translator mod has two submods, one is greptime and the other is postgres. Many of their codes are similar, so I am curious whether there is a dialect of greptime or just MySQL.

Good point. I renamed the greptime to mysql.

[codecov]

Codecov Report

Attention: 51 lines in your changes are missing coverage. Please review.

Comparison is base (364754a) 85.85% compared to head (ec0ed3c) 85.38%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3206      +/-   ##
==========================================
- Coverage   85.85%   85.38%   -0.48%     
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  Files         844      847       +3     
  Lines      138609   138767     +158     
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- Hits       119009   118489     -520     
- Misses      19600    20278     +678     

[fengjiachun]

LGTM