Translate N1QL Query to Java SDK

Java SDK
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#1

Hi,

I’m using couchbase 6.5.1 and java sdk 2.7.1
I have compare speed between using N1QL and SDK, it’s much faster using SDK
(N1QL insert vs SDK upsert)
I have merge query below:

MERGE INTO myBucket AS target
USING [
{ “name”:“test”}
] AS source
ON key “TEST::1”
WHEN MATCHED THEN
UPDATE SET target.name= source.name
WHEN NOT MATCHED THEN
INSERT (
{
“name”: source.name,
} )
returning target.*;

Is it possible change this N1QL to SDK version?

Thanks

#2

As you already have key,
Get the document.
If present update with cas else insert

#3

Thanks @vsr1 for your quick response

So there’s no direct function for merge using sdk?

Do you have java sample code for that update cas?Is it the same as mutateIn?

Thanks

#4

update (SDK replace), MERGE is SQL statement (no SDK operations)

1 Like
#5

how about ARRAY DISTINCT, is it applicable using KV or sdk? @vsr1

#6

All these are N1QL syntax https://docs.couchbase.com/server/current/n1ql/n1ql-language-reference/index.html

#7

Hi @vsr1,

I have implemented that logic but now having concurrent sequence issue.

My sample data is: (a,b,c,d,e) using same doc id

My CAS logic is when getting CASMismatchException, I will do sleep for 1 sec then retry.

When I tried to run the code, it saves all the data but the sequence is wrong (a,c,e,d,b)

The problem is that I need the data sequential

If I change the method to sync it can solve the sequential problem, but the performance is not as fast as async.

Do you have any insights for this?

Thanks

#8

not sure what do u mean by sequence is it array

#9

let say i have 5 concurrent message in kafka to be processed with sequence inside doc :
{ “seq”:”a” ,… } { “seq”:”b” ,…} { “seq”:”c” ,…} { “seq”:”d”,…} { “seq”:”e”,…}
this will be appended into 1 couchbase doc id with expected result:

{ [{“seq”:”a”}, {“seq”:”b”},…e ]}

#10

If you are using SUBDOC array insert ot array append will not work.
You need to get whole array and construct by inserting right order and write . If cas miss match you need to repeat.

or take array and sort in seq use it