no output when join tables with multiple columns

[young-mu]

I found when join tables with multiple columns, if the sequence of columns in the two tables are different, there will be no output.

---

You can reproduce this bug by the example below. I join two tables using two columns _measurement and _time.

In table1, the sequence of these two columns is _time, _measurement,
In table2, the sequence is _time, _measurement,
In table3, the sequence is _measurement, _time,

There is no output when joining table2 and table3.

import "csv"

csvData1 = "
#group,false,false,false,false                                                                                                                                                                  
#datatype,string,long,dateTime:RFC3339,string
#default,,,,
,result,table,_time,_measurement
,,0,2021-02-22T16:00:00Z,0
,,0,2021-02-23T16:00:00Z,0
"

csvData2 = "
#group,false,false,false,false,false
#datatype,string,long,dateTime:RFC3339,string,string
#default,,,,,
,result,table,_time,_measurement,sn
,,0,2021-02-22T16:00:00Z,0,GLD18-0
,,0,2021-02-24T16:00:00Z,0,GLD18-0
"

csvData3 = "
#group,false,false,false,false
#datatype,string,long,string,dateTime:RFC3339
#default,,,,
,result,table,_measurement,_time
,,0,0,2021-02-22T16:00:00Z
,,0,0,2021-02-24T16:00:00Z
"

table1 = csv.from(csv: csvData1)
table2 = csv.from(csv: csvData2)
table3 = csv.from(csv: csvData3)

table12= join(tables: { table1: table1, table2: table2 }, on: ["_measurement", "_time"], method: "inner")
  |> yield(name: "table12")

table13= join(tables: { table1: table1, table3: table3 }, on: ["_measurement", "_time"], method: "inner")
  |> yield(name: "table13") // no output

[dgsardina]

Same issue on OSS Version 2.0.4