fix: count column aliases only once

internal/compiler/output_columns.go

@@ -661,6 +661,7 @@ func findColumnForRef(ref *ast.ColumnRef, tables []*Table, selectStatement *ast.
 	}
 
 	var found int
+	var foundResTarget *ast.ResTarget
 	for _, t := range tables {
 		if alias != "" && t.Rel.Name != alias {
 			continue
@@ -686,7 +687,10 @@ func findColumnForRef(ref *ast.ColumnRef, tables []*Table, selectStatement *ast.
 				continue
 			}
 			if resTarget.Name != nil && *resTarget.Name == name {
-				found++
+				if resTarget != foundResTarget {
+					found++
+					foundResTarget = resTarget
+				}
 			}
 		}
 	}

internal/endtoend/testdata/join_group_order/postgresql/query.sql

@@ -0,0 +1,17 @@
+-- Example queries for sqlc
+CREATE TABLE authors (
+    id   INT
+);
+
+CREATE TABLE books (
+    id   INT,
+    author_id INT,
+    price INT
+);
+
+-- name: ListAuthorsByCheapestBook :many
+SELECT
+    author_id, min(b.price) as min_price
+From books b inner join authors a on a.id = b.author_id
+GROUP BY b.author_id
+ORDER BY min_price;

internal/endtoend/testdata/join_group_order/postgresql/sqlc.yaml

@@ -0,0 +1,7 @@
+version: 1
+packages:
+  - path: "go"
+    name: "querytest"
+    engine: "postgresql"
+    schema: "query.sql"
+    queries: "query.sql"