How to read from array of low cardinality column?

[kant777]

How to read from array of low cardinality string column?

Below is the parts of the code I used to Read LowCardinality Column

tagsKey = proto.ColStr{}
tagsKeyLC = proto.ColLowCardinality{
	Index: &tagsKey,
}
tagsKeyArr = proto.ColArr{
	Data: &tagsKeyLC,
}

Result: proto.Results{
	{Name: "tags.key", Data: &tagsKeyArr},
},

I get the following error

panic: decode block: decode block: target: tags.key: decode data: got version 30, expected 1

any example?

[ernado]

Now you can see TestArrLowCardinalityStr:

str := &proto.ColStr{}
idx := &proto.ColLowCardinality{Index: str}
col := &proto.ColArr{Data: idx}

Use col to read of Array(LowCardinality(String)) column.

Ergonomics will improve soon with go1.18 and generics.

[kant777]

@ernado so there are code changes? I need to download the latest code? looks like I am using the correct the syntax..Also another question is general. I see Result and onResult..do I need to put the same code for Result and OnResult if I were to read to all the blocks that are available as a result of my query?

[ernado]

Oh, can you please provide a full test case like we have in query_test.go?

You need to set OnResult when you expect more that single data block as query result.

[ernado]

Looks like there is a bug.
#30

Please usse https://github.com/ClickHouse/clickhouse-go for now, should be easier.

[ernado]

Should work in v0.18.2