Can I pass arguments to CQL?

Question

Hi,
I'm planning to join my events with a table source using CQL. But I dont want to query the entire table source because it's too big, instead, I want to put a "where" condition in my CQL so that it will only fetch a subset of records from the table source. But my "where" condition is dynamic. I want to pass variables to my "where" condition. Something like:
"SELECT * FROM STREAM1 [NOW], TABLE1 WHERE STREAM1.ID=TABLE1.ID AND TABLE1.KEY > #START_KEY# AND TABLE1.KEY < #END_KEY#"
where the #START_KEY# and #END_KEY# are the variables/arguments that I will pass to the CQL. Is there a mechanism like this?
Thanks,
Aurelio

Answer 1

Here is another way of doing this -
1) Create a (local) cache and store the variables START_KEY and END_KEY
2) Join the input stream Stream1 with cache C as follows -
RSTREAM (
SELECT
S.*,
C.START_KEY,
C.END_KEY
FROM
STREAM1[NOW] AS S,
Cache AS C
3) Stream the output of the above query into a channel Stream2
Then, use the query
RSTREAM (
SELECT
FROM
STREAM2 [NOW],
TABLE1
WHERE
STREAM2.ID=TABLE1.ID AND
TABLE1.KEY > STREAM2.START_KEY AND
TABLE1.KEY < STREAM2.END_KEY
4) Change the values of START_KEY and END_KEY in the cache dynamically. Subsequent events on Stream1 will pick up the changed values