Adding upstream version 10.5.6.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tests/dialects/test_bigquery.py

@@ -6,6 +6,8 @@ class TestBigQuery(Validator):
     dialect = "bigquery"
 
     def test_bigquery(self):
+        self.validate_identity("SELECT STRUCT<ARRAY<STRING>>(['2023-01-17'])")
+        self.validate_identity("SELECT * FROM q UNPIVOT(values FOR quarter IN (b, c))")
         self.validate_all(
             "REGEXP_CONTAINS('foo', '.*')",
             read={"bigquery": "REGEXP_CONTAINS('foo', '.*')"},
@@ -41,6 +43,15 @@ class TestBigQuery(Validator):
                 "spark": r"'/\\*.*\\*/'",
             },
         )
+        self.validate_all(
+            r"'\\'",
+            write={
+                "bigquery": r"'\\'",
+                "duckdb": r"'\'",
+                "presto": r"'\'",
+                "hive": r"'\\'",
+            },
+        )
         self.validate_all(
             R'R"""/\*.*\*/"""',
             write={