Sub-query example query

[jbguerraz]

Error 2/3

{
"batchSize":20480,
"columns":["__time","channel","cityName","comment","count","countryIsoCode","diffUrl","flags","isAnonymous","isMinor","isNew","isRobot","isUnpatrolled","metroCode","namespace","page","regionIsoCode","regionName","sum_added","sum_commentLength","sum_deleted","sum_delta","sum_deltaBucket","user"],
"dataSource":{"type":"query","query":{"queryType":"scan","dataSource":{"type":"table","name":"A"},"columns":["AT"],"intervals":{"type":"intervals","intervals":["1980-06-12T22:30:00.000Z/2020-01-26T23:00:00.000Z"]}}},
"filter":{"dimension":"countryName","extractionFn":{"locale":"","type":"lower"},"type":"selector","value":"france"},
"intervals":{"type":"intervals","intervals":["1980-06-12T22:30:00.000Z/2020-01-26T23:00:00.000Z"]},
"limit":10,
"order":"descending",
"queryType":"scan"
}

The above querying is failing when executed directly on Apache Druid with below error. I think this is a query error and not a bug in code. Perhaps we just need to fix this query.

Time-ordering on scan queries is only supported for queries with segment specs of type MultipleSpecificSegmentSpec or SpecificSegmentSpec...a [MultipleIntervalSegmentSpec] was received instead.

This query must have never worked indeed. Introduced here: 4995687#diff-7c1b8c5172fe7687c2af90f55f18e7e5eacf13af953ccc2bbeb5de3fa56e2688R25

Probably used only to debug the object model of the query (specific to circular dependency) rather than for getting results. We should fix it so it is valid and return results but still test the sub-query case

Originally posted by @jbguerraz in #13 (comment)

[saketbairoliya2]

Do we've any updates on this? @jbguerraz

[saketbairoliya2]

As I understand the Load() function returns correct request body but when making call to Execute() function, we get error about the null value.

ErrorMessage:Cannot construct instance of org.apache.druid.query.QueryDataSource, problem: 'query' must be nonnull .....

[saketbairoliya2]

For context - I'm trying this query:

{
	"dataSource": {
		"query": {
			"aggregations": [{
				"fieldName": "count",
				"name": "count",
				"type": "longSum"
			}],
			"dataSource": {
				"name": "dc_94b4f5fdfde940979b79c50539d8322a_b42fde98efed4e638a0016b34b3c10cf_dataset_pre",
				"type": "table"
			},
			"dimension": {
				"dimension": "string_value",
				"type": "default"
			},
			"filter": {
				"fields": [{
						"dimension": "_split_name_",
						"type": "selector",
						"value": "train"
					},
					{
						"dimension": "column_name",
						"type": "selector",
						"value": "addressState"
					}
				],
				"type": "and"
			},
			"granularity": "day",
			"intervals": {
				"intervals": [
					"2022-10-07T00:00:00Z/P1W"
				],
				"type": "intervals"
			},
			"metric": {
				"metric": "count",
				"type": "numeric"
			},
			"queryType": "topN",
			"threshold": 100
		},
		"type": "query"
	},
	"granularity": "day",
	"intervals": {
		"intervals": [
			"2022-10-07T00:00:00Z/P1W"
		],
		"type": "intervals"
	},
	"queryType": "timeseries"
}

[saketbairoliya2]

This was the query sent to druid, why do we've a - here? To avoid circular dependency?

{
	"queryType": "timeseries",
	"dataSource": {
		"type": "query",
		"-": {
			"queryType": "topN",
			"dataSource": {
				"type": "table",
				"name": "dc_94b4f5fdfde940979b79c50539d8322a_b42fde98efed4e638a0016b34b3c10cf_dataset_pre"
			},
			"intervals": {
				"type": "intervals",
				"intervals": ["2022-10-07T00:00:00Z/P1W"]
			},
			"dimension": {
				"type": "default",
				"dimension": "string_value"
			},
			"metric": {
				"type": "numeric",
				"metric": "count"
			},
			"threshold": 100,
			"filter": {
				"type": "and",
				"fields": [{
					"type": "selector",
					"dimension": "__split_name__",
					"value": "train"
				}, {
					"type": "selector",
					"dimension": "column_name",
					"value": "addressState"
				}]
			},
			"granularity": "day",
			"aggregations": [{
				"type": "longSum",
				"name": "count",
				"fieldName": "count"
			}]
		}
	},
	"intervals": {
		"type": "intervals",
		"intervals": ["2022-10-07T00:00:00Z/P1W"]
	},
	"granularity": "day"
}

[vigith]

we haven't tested sub-querying.

[jbguerraz]

As discussed on Slack this comes from this change: b1a5a24#diff-8086ca5b4c31b5fcab1a5f0afc76bea40123e6a3852ecc1a19e1bba87e0a4b68R11

Have to restore it as it was in 4995687#diff-79e56959c31d638b4bdc3513e79921e69eefeb66836c1e985dbaa9585f8c968aR12

Probably it could be related to #78

[bourbonkk]

@saketbairoliya2 @jbguerraz @vigith
I wrote the test code for the subquery in #82 PR

There were code modifications.
Query struct : "-,omitempty" -> "query,omitempty"

type Query struct {
	Base
	Query builder.Query `json:"query,omitempty"`
}

This is necessary to make a subquery.

so please check it out.