In YugabyteDB YCQL, the SELECT statement must have a FROM clause. However, some queries don’t require any table.
Example:
ycqlsh> SELECT currenttimestamp();
SyntaxException: Feature Not Supported
SELECT currenttimestamp();
At location: (1.26)
(ql error -14)
If you are familiar with Oracle, then you’ll know that for this situation it provides you with the DUAL table which is a special table that belongs to the schema of the user SYS but it is accessible to all users.
There isn’t a DUAL table in YCQL, but you can use the system.local table instead. It will always return a single row and is a perfect replacement for the DUAL table.
ycqlsh> SELECT currenttimestamp() FROM system.local;
currenttimestamp()
---------------------------------
2022-06-22 13:39:02.142000+0000
(1 rows)
Have Fun!