Scylla: Support Datetime functions

[tzach]

Installation details
Scylla version (or git commit hash): 2.0

Add support for Datetime conversion functions

• currentTimestamp
• currentDate
• currentTime
• currentTimeUUID

Example:

SELECT * FROM myTable WHERE date >= currentDate() - 2d

Source:
http://cassandra.apache.org/doc/latest/cql/functions.html#datetime-functions

[slivne]

need to validate / impl the following as well

Function name | Input type | Description
-- | -- | --
toDate | timeuuid | Converts the timeuuid argument into a date type
toDate | timestamp | Converts the timestamp argument into a date type
toTimestamp | timeuuid | Converts the timeuuid argument into a timestamp type
toTimestamp | date | Converts the date argument into a timestamp type
toUnixTimestamp | timeuuid | Converts the timeuuid argument into a bigInt raw value
toUnixTimestamp | timestamp | Converts the timestamp argument into a bigInt raw value
toUnixTimestamp | date | Converts the date argument into a bigInt raw value
dateOf | timeuuid | Similar to toTimestamp(timeuuid) (DEPRECATED)
unixTimestampOf | timeuuid | Similar to toUnixTimestamp(timeuuid) (DEPRECATED)

[glommer]

FYI: We just had an user in the users slack looking for that today

[hagrid-the-developer]

What version of C* do they use? I tried the example with -2d and it didn't work in Cassandra-3.11.2:

cqlsh:xyz> select * from dt where dt >= currentDate() - 2d;
SyntaxException: line 1:43 mismatched input '-' expecting EOF (...where dt >= currentData() [-]...)

C* documentation isn't clear whether only d is supported, probably ms, s, M, h, d, w, m, y would make sense.

It seems that toDate(.), titimestamp(.), toUnixTimestamp aren't supported by Scylla.