Filter map by key-value pairs

Client Libraries Go Client
1

Is it possible to use expression filters on maps to select records with a specific map key matching a specific value? I’m only seeing options in the API for separate MAPKEYS and MAPVALUES filters. Is there a way to accomplish this with expressions, or would I just need to do it in a UDF or in post processing on the application side?

2

Not sure that I follow, I think you want to find a record where a particular map bin contains a particular key, value pair where the key equals some key and the value equals some value. If not, please try to clarify your request, maybe with a code example.

For matching a key and value, you should be able to use the map_get_by_key expression.

Such an expression would look something like this:

// Filter to return record where the map stored in the bin named "binName" contains the key
// "mapKey" and the value stored at that they equals 5.
eq(
    map_get_by_key(
        type.integer, context, result_type.value, as_exp_str("mapKey"), bin_map("binName")),
    as_exp_int(5))
3

Yes, that’s what I’m trying to do. I figured out how to do this in the Go client, but it took a while looking at the expression tests and trying different things from that. It looks the same as what you shared, so looks like this is the right way.

queryPolicy.FilterExpression = aerospike.ExpEq(
    aerospike.ExpMapGetByKey(aerospike.MapReturnType.VALUE, aerospike.ExpTypeINT, aerospike.ExpStringVal("some_key"), aerospike.ExpMapBin("bin_name")),
    aerospike.ExpIntVal(5),
)
1 Like
4

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