BigQuery: Unreserve KEY keyword (sqlfluff#5703)

src/sqlfluff/dialects/dialect_bigquery_keywords.py

@@ -51,7 +51,6 @@
 INTO
 IS
 JOIN
-KEY
 LATERAL
 LEFT
 LIKE
@@ -177,6 +176,7 @@
 INOUT
 INSERT
 INTEGRATION
+KEY
 ITERATE
 LANGUAGE
 LARGE

test/fixtures/dialects/bigquery/select.sql

@@ -0,0 +1 @@
+SELECT 'metadata' AS key from foo;

test/fixtures/dialects/bigquery/select.yml

@@ -0,0 +1,24 @@
+# YML test files are auto-generated from SQL files and should not be edited by
+# hand. To help enforce this, the "hash" field in the file must match a hash
+# computed by SQLFluff when running the tests. Please run
+# `python test/generate_parse_fixture_yml.py`  to generate them after adding or
+# altering SQL files.
+_hash: dee0a6c0271b2be54f6c70ff6062083e5b2d7842c80a81597715b6abb523d67c
+file:
+  statement:
+    select_statement:
+      select_clause:
+        keyword: SELECT
+        select_clause_element:
+          quoted_literal: "'metadata'"
+          alias_expression:
+            keyword: AS
+            naked_identifier: key
+      from_clause:
+        keyword: from
+        from_expression:
+          from_expression_element:
+            table_expression:
+              table_reference:
+                naked_identifier: foo
+  statement_terminator: ;