[SOLVED] Invalid input 'p' for cypher query with ' CALL apoc.do.when()'

Invalid input 'p' for cypher query with ' CALL apoc.do.when()'

I get the following error for my cypher query (quoted below):

Invalid input 'p': expected 
    'n/N' or 's/S' 
    (line 1, column 116 (offset: 115))

"OPTIONAL MATCH (m:MeasurementSite)-[*2]-(v:Val) 
    WHERE ID(m) = $meter 
    AND v.d < $end 
    AND v.d > $start 
    WITH v, CALL 
        apoc.do.when(v IS NOT NULL, 
            'RETURN abs(toInteger(apoc.temporal.format(duration.inDays($date, $d), \'dd\')))', 
            'RETURN null',
            {d: v.d, date: $date}) AS dist 
    RETURN v, dist;"

The referenced p is the second character in apoc.

Link for CALL is here. Does anybody know the problem and is it related to (wrong) quotes?

Seems like you can start a query with CALL apoc.do.when(), but you cannot use it in somewhere in the middle of a query.

Working on version 4.

Solution

The CALL clause cannot be used inside other clauses.

In addition, your WHERE clause effectively filters out v values that are NULL, so:

your query doesn't need to test whether v is NULL, and
your MATCH doesn't need to be OPTIONAL either.

Therefore, this should be good enough:

MATCH (m:MeasurementSite)-[*2]-(v:Val) 
WHERE ID(m) = $meter 
  AND v.d < $end 
  AND v.d > $start
RETURN v, {d: v.d, date: $date} AS dist;