Merge "tp: update sqlite3_vtab_distinct handling based on latest documentation" into mainHEADmastermain

2 files changed, 32 insertions, 4 deletions

diff --git a/src/trace_processor/sqlite/db_sqlite_table.cc b/src/trace_processor/sqlite/db_sqlite_table.cc
index 736af92d1..cc4f545da 100644
--- a/src/trace_processor/sqlite/db_sqlite_table.cc
+++ b/src/trace_processor/sqlite/db_sqlite_table.cc
@@ -54,9 +54,6 @@
 namespace perfetto::trace_processor {
 namespace {
 
-// TODO(b/341230981): Enable after it's fixed.
-static constexpr bool kEnableDistinct = false;
-
 std::optional<FilterOp> SqliteOpToFilterOp(int sqlite_op) {
   switch (sqlite_op) {
     case SQLITE_INDEX_CONSTRAINT_EQ:
@@ -574,7 +571,7 @@ int DbSqliteModule::BestIndex(sqlite3_vtab* vtab, sqlite3_index_info* info) {
 
   // Distinct:
   idx_str += "D";
-  if (ob_idxes.size() == 1 && kEnableDistinct) {
+  if (ob_idxes.size() == 1 && PERFETTO_POPCOUNT(info->colUsed) == 1) {
     switch (sqlite3_vtab_distinct(info)) {
       case 0:
       case 1:
diff --git a/test/trace_processor/diff_tests/syntax/table_tests.py b/test/trace_processor/diff_tests/syntax/table_tests.py
index 7de63e9d4..5785b6f8a 100644
--- a/test/trace_processor/diff_tests/syntax/table_tests.py
+++ b/test/trace_processor/diff_tests/syntax/table_tests.py
@@ -178,6 +178,37 @@ class PerfettoTable(TestSuite):
         3073,8,4529,8
         """))
 
+  def test_distinct_multi_column(self):
+    return DiffTestBlueprint(
+        trace=TextProto(''),
+        query="""
+        CREATE PERFETTO TABLE foo AS
+        WITH data(a, b) AS (
+          VALUES
+            -- Needed to defeat any id/sorted detection.
+            (2, 3),
+            (0, 2),
+            (0, 1)
+        )
+        SELECT * FROM data;
+
+        CREATE TABLE bar AS
+        SELECT 1 AS b;
+
+        WITH multi_col_distinct AS (
+          SELECT DISTINCT a FROM foo CROSS JOIN bar USING (b)
+        ), multi_col_group_by AS (
+          SELECT a FROM foo CROSS JOIN bar USING (b) GROUP BY a
+        )
+        SELECT
+          (SELECT COUNT(*) FROM multi_col_distinct) AS cnt_distinct,
+          (SELECT COUNT(*) FROM multi_col_group_by) AS cnt_group_by
+        """,
+        out=Csv("""
+        "cnt_distinct","cnt_group_by"
+        1,1
+        """))
+
   def test_limit(self):
     return DiffTestBlueprint(
         trace=TextProto(''),