fix: quote column name in prom query filter (#1083)

## Rationale
PromQL query should be case-sensitive for  column name

## Detailed Changes
- Use `ident` when construct filter.

## Test Plan
Update integration tests and UT

integration_tests/prom/remote-query.py

@@ -31,23 +31,23 @@ def prepare_data(ts):
 CREATE TABLE if not exists `{}` (
     `t` timestamp NOT NULL,
     `tag1` string TAG,
-    `tag2` string TAG,
+    `TAG2` string TAG,
     `value` double NOT NULL,
     `VALUE2` double NOT NULL,
     timestamp KEY (t)
 );
         """.format(t))
 
     execute_sql("""
-insert into {}(t, tag1, tag2, value, VALUE2)
+insert into {}(t, tag1, TAG2, value, VALUE2)
 values
 ({}, "v1", "v2", 1, 2),
 ({}, "v1", "v2", 11, 22)
     ;
     """.format(table, ts-5000, ts))
 
     execute_sql("""
-insert into {}(t, tag1, tag2, value, VALUE2)
+insert into {}(t, tag1, TAG2, value, VALUE2)
 values
 ({}, "v1", "v2", 10, 20),
 ({}, "v1", "v2", 110, 220)
@@ -60,11 +60,15 @@ def remote_query(ts):
 
     r = execute_pql(table + '{tag1="v1"}[5m]')
     result = r['data']['result']
-    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'tag2': 'v2'}, 'values': [[ts-5, '1'], [ts, '11']]}]
+    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'TAG2': 'v2'}, 'values': [[ts-5, '1'], [ts, '11']]}]
+
+    r = execute_pql(table + '{TAG2="v2"}[5m]')
+    result = r['data']['result']
+    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'TAG2': 'v2'}, 'values': [[ts-5, '1'], [ts, '11']]}]
 
     r = execute_pql(table + '{tag1=~"v1"}[5m]')
     result = r['data']['result']
-    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'tag2': 'v2'}, 'values': [[ts-5, '1'], [ts, '11']]}]
+    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'TAG2': 'v2'}, 'values': [[ts-5, '1'], [ts, '11']]}]
 
     r = execute_pql(table + '{tag1!="v1"}[5m]')
     result = r['data']['result']
@@ -77,12 +81,12 @@ def remote_query(ts):
     # uppercase field
     r = execute_pql(table + '{tag1="v1",__ceresdb_field__="VALUE2"}[5m]')
     result = r['data']['result']
-    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'tag2': 'v2'}, 'values': [[ts-5, '2'], [ts, '22']]}]
+    assert result == [{'metric': {'__name__': table, 'tag1': 'v1', 'TAG2': 'v2'}, 'values': [[ts-5, '2'], [ts, '22']]}]
 
     # uppercase table
     r = execute_pql(table2 + '{tag1="v1"}[5m]')
     result = r['data']['result']
-    assert result == [{'metric': {'__name__': table2, 'tag1': 'v1', 'tag2': 'v2'}, 'values': [[ts-5, '10'], [ts, '110']]}]
+    assert result == [{'metric': {'__name__': table2, 'tag1': 'v1', 'TAG2': 'v2'}, 'values': [[ts-5, '10'], [ts, '110']]}]
 
 def main():
     ts = now()

query_frontend/src/promql/remote.rs

@@ -8,7 +8,7 @@ use common_types::{schema::Schema, time::TimeRange};
 use datafusion::{
     logical_expr::LogicalPlanBuilder,
     optimizer::utils::conjunction,
-    prelude::{col, lit, regexp_match, Expr},
+    prelude::{ident, lit, regexp_match, Expr},
     sql::{planner::ContextProvider, TableReference},
 };
 use prom_remote_api::types::{label_matcher, LabelMatcher, Query};
@@ -95,16 +95,17 @@ fn normalize_matchers(matchers: Vec<LabelMatcher>) -> Result<(String, String, Ve
             NAME_LABEL => metric = Some(m.value),
             FIELD_LABEL => field = Some(m.value),
             _ => {
+                let col_name = ident(&m.name);
                 let expr = match m.r#type() {
-                    label_matcher::Type::Eq => col(m.name).eq(lit(m.value)),
-                    label_matcher::Type::Neq => col(m.name).not_eq(lit(m.value)),
+                    label_matcher::Type::Eq => col_name.eq(lit(m.value)),
+                    label_matcher::Type::Neq => col_name.not_eq(lit(m.value)),
                     // https://github.com/prometheus/prometheus/blob/2ce94ac19673a3f7faf164e9e078a79d4d52b767/model/labels/regexp.go#L29
                     label_matcher::Type::Re => {
-                        regexp_match(vec![col(m.name), lit(format!("^(?:{})$", m.value))])
+                        regexp_match(vec![col_name, lit(format!("^(?:{})$", m.value))])
                             .is_not_null()
                     }
                     label_matcher::Type::Nre => {
-                        regexp_match(vec![col(m.name), lit(format!("^(?:{})$", m.value))]).is_null()
+                        regexp_match(vec![col_name, lit(format!("^(?:{})$", m.value))]).is_null()
                     }
                 };
 
@@ -215,7 +216,7 @@ Query(QueryPlan { df_plan: Sort: cpu.tsid ASC NULLS FIRST, cpu.time ASC NULLS FI
                 ("a", "1", Type::Eq),
                 ("b", "2", Type::Neq),
                 ("c", "3", Type::Re),
-                ("d", "4", Type::Nre),
+                ("D", "4", Type::Nre),
                 (NAME_LABEL, "cpu", Type::Eq),
             ]);
 
@@ -226,7 +227,7 @@ Query(QueryPlan { df_plan: Sort: cpu.tsid ASC NULLS FIRST, cpu.time ASC NULLS FI
                 r#"a = Utf8("1")
 b != Utf8("2")
 regexpmatch(c, Utf8("^(?:3)$")) IS NOT NULL
-regexpmatch(d, Utf8("^(?:4)$")) IS NULL"#,
+regexpmatch(D, Utf8("^(?:4)$")) IS NULL"#,
                 filters
                     .iter()
                     .map(|f| f.to_string())