Hello all,
I’m trying to reindex from a collection to a new collection with a different
schema, using streaming expressions. I can’t use REINDEXCOLLECTION directly,
because I need to process documents a bit.
I couldn’t figure out 3 simple, related things for hours so forgive me if I
just ask.
1) Is there a way to duplicate the value of a field of an incoming tuple into
two fields?
I tried the select expression:
select(
echo("Hello"),
echo as echy, echo as echee
)
But when I use the same field twice, only the last “as” takes effect, it
doesn’t copy the value to two fields:
{
"result-set": {
"docs": [
{
"echee": "Hello"
},
{
"EOF": true,
"RESPONSE_TIME": 0
}
]
}
}
I accomplished this by using leftOuterJoin, with same exact stream in
left and right, joining on itself with different field names. But this has the
penaly of executing the same stream twice, It’s no problem for small streams
but in my case there will be a couple hundred million tuples coming from the
stream.
2) Is there a way to “feed” one stream’s output to two different streams? Like
feeding output of a stream source to two different stream decorator without
executing the same stream twice?
3) Does the “let” stream hold its entire content in memory when a stream is
assigned to a variable, or does it stream continuously too? If not, I imagine
it can be used for my question 2.
I’m glad that Solr has streaming expressions.
--ufuk yilmaz
Sent from Mail for Windows 10
