[influxdb/v2] differing influxql results when comparing field to signed vs unsigned integer

[jdstrand]

An external reporter sent an issue regarding InfluxQL queries in 2.x. Using 2.7.6, comparing a field to a signed integer works as expected. Eg:

$  export V1AUTH=$(echo -n "anything:$TOKEN" | base64 --wrap 0)

# generate some line protocol 
$ cat > file.lp <<EOM
t0,t0_tag0=initTag t0_f0=0i 1715694000
t0,t0_tag0=initTag t0_f0=1i 1715694001
t0,t0_tag1=initTag t0_f0=0i 1715694000
EOM

# write
$ curl -H "Authorization: Basic $V1AUTH" -X POST "$URL/write?db=test1&precision=s" --data-binary @./file.lp
$

# queries
# ok
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test1&rp=autogen" --data-urlencode "q=select * from t0"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

# ok with signed ints
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test1&rp=autogen" --data-urlencode "q=select * from t0 where (1) < (17693) ORDER BY ASC LIMIT 2147483647"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test1&rp=autogen" --data-urlencode "q=select * from t0 where (t0_f0) < (17693) ORDER BY  ASC LIMIT 2147483647"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

But comparing a field to an unsigned integer does not:

$  export V1AUTH=$(echo -n "anything:$TOKEN" | base64 --wrap 0)

# generate some line protocol 
$ cat > file2.lp <<EOM
t0,t0_tag0=initTag t0_f0=0u 1715694000
t0,t0_tag0=initTag t0_f0=1u 1715694001
t0,t0_tag1=initTag t0_f0=0u 1715694000
EOM

# write
$ curl -H "Authorization: Basic $V1AUTH" -X POST "$URL/write?db=test2&precision=s" --data-binary @./file2.lp
$

# queries
# ok
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test2&rp=autogen" --data-urlencode "q=select * from t0"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

# this query ok with unsigned int
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test2&rp=autogen" --data-urlencode "q=select * from t0 where (1u) < (17693u) ORDER BY ASC LIMIT 2147483647"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

# but this one is NOT
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test2&rp=autogen" --data-urlencode "q=select * from t0 where (t0_f0) < (17693u) ORDER BY ASC LIMIT 2147483647"
$

# ok if change 17693u to 17693
$ curl -H "Authorization: Basic $V1AUTH" -H "Accept: application/csv" -X POST "$URL/query?db=test2&rp=autogen" --data-urlencode "q=select * from t0 where (t0_f0) < (17693) ORDER BY ASC LIMIT 2147483647"
name,tags,time,t0_f0,t0_tag0,t0_tag1
t0,,1715694000000000000,0,initTag,
t0,,1715694000000000000,0,,initTag
t0,,1715694001000000000,1,initTag,

InfluxDB 1.x does not support unsigned integers (see https://docs.influxdata.com/influxdb/v1/write_protocols/line_protocol_reference/ and https://docs.influxdata.com/enterprise_influxdb/v1/write_protocols/line_protocol_reference/ vs https://docs.influxdata.com/influxdb/v2/reference/syntax/line-protocol/). It operates correctly with signed integers.

cc @davidby-influx