From d55bb2029878d1bdeddab9ce3025fefbd05860d5 Mon Sep 17 00:00:00 2001
From: basili4-1982 <1531789+basili4-1982@users.noreply.github.com>
Date: Sat, 22 Aug 2026 02:24:58 +0300
Subject: [PATCH] feat(parser): ClickHouse array/tuple element access via dot
 (d.1)

Allow a numeric component after a period in ClickHouse qualified identifiers
(alias.1, tuple.2) for array/tuple element access. Restricted to the ClickHouse
dialect so Postgres qualified columns stay unchanged.

Regression: TestClickHouseArrayElementAccess.
---
 pkg/sql/parser/clickhouse_array_dot_test.go | 41 +++++++++++++++++++++
 pkg/sql/parser/expressions_literal.go       |  3 +-
 2 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 pkg/sql/parser/clickhouse_array_dot_test.go

diff --git a/pkg/sql/parser/clickhouse_array_dot_test.go b/pkg/sql/parser/clickhouse_array_dot_test.go
new file mode 100644
index 00000000..430f09e6
--- /dev/null
+++ b/pkg/sql/parser/clickhouse_array_dot_test.go
@@ -0,0 +1,41 @@
+// Copyright 2026 GoSQLX Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package parser_test
+
+import (
+	"testing"
+
+	"github.com/ajitpratap0/GoSQLX/pkg/gosqlx"
+	"github.com/ajitpratap0/GoSQLX/pkg/sql/keywords"
+)
+
+// Regression: ClickHouse array/tuple element access via dot-notation (d.1, t.2)
+// must parse. Previously a numeric component after '.' raised E2004.
+func TestClickHouseArrayElementAccess(t *testing.T) {
+	tests := []string{
+		`SELECT d.1 FROM t ARRAY JOIN arr AS d`,
+		`SELECT a.x FROM t ARRAY JOIN a`,
+		`SELECT arr[1] FROM t`,
+	}
+	for _, sql := range tests {
+		tree, err := gosqlx.ParseWithDialect(sql, keywords.DialectClickHouse)
+		if err != nil {
+			t.Fatalf("parse %q failed: %v", sql, err)
+		}
+		if got := tree.SQL(); got != sql {
+			t.Errorf("SQL() = %q, want %q", got, sql)
+		}
+	}
+}
diff --git a/pkg/sql/parser/expressions_literal.go b/pkg/sql/parser/expressions_literal.go
index 04516108..938f6005 100644
--- a/pkg/sql/parser/expressions_literal.go
+++ b/pkg/sql/parser/expressions_literal.go
@@ -194,10 +194,11 @@ func (p *Parser) parsePrimaryExpression() (ast.Expression, error) {
 					Pos:   identPos,
 				}
 				p.advance()
-			} else if p.isIdentifier() || p.isNonReservedKeyword() {
+			} else if p.isIdentifier() || p.isNonReservedKeyword() || (p.dialect == string(keywords.DialectClickHouse) && p.isNumericLiteral()) {
 				// Handle table.column (qualified identifier).
 				// isNonReservedKeyword covers reserved words valid as column
 				// names after a dot, e.g. table.KEY, schema.INDEX, alias.VIEW.
+				// ClickHouse also allows numeric element access: d.1, tuple.2.
 				ident = &ast.Identifier{
 					Table: ident.Name,
 					Name:  p.currentToken.Token.Value,