Postgres Compatible

ClapDB query SQL will fully compatibility with PostgreSQL’s SQL, and current state can be checked in below chart.

According to PostgreSQL tutorial

PostgreSQL Command	ClapDB Free	ClapDB Pro	ClapDB Enterpise
Select
Column aliases
Order by
Select Distinct
Where
AND operator
OR operator
Limit
Fetch
In
Between
Like
Is Null
Joins
Table aliases
Inner Join
Left Join
Self-join
Full Outer Join
Cross join
Natural Join
Group By
Having
Union
Intersect
Except
Grouping Sets
Cube
Rollup
Subquery
Correlated Subquery
ANY
ALL
EXIST
PostgreSQL CTE
Recursive query using CTEs