[Snowflake] Support of cast expr (#3825)

Author: gaoshihang

sql/snowflake/SnowflakeParser.g4

@@ -3636,6 +3636,7 @@ builtin_function
     | IDENTIFIER
     | FLATTEN
     | SPLIT_TO_TABLE
+    | CAST
     ;
 
 list_operator
@@ -3740,7 +3741,7 @@ expr
 //    | expr time_zone
     | expr COLON_COLON data_type //cast
     | expr over_clause
-    | CAST LR_BRACKET expr AS data_type RR_BRACKET
+    | cast_expr
     | json_literal
     | binary_builtin_function LR_BRACKET expr COMMA expr RR_BRACKET
     | binary_or_ternary_builtin_function LR_BRACKET expr COMMA expr (COMMA expr)* RR_BRACKET
@@ -3767,6 +3768,10 @@ try_cast_expr
     : TRY_CAST LR_BRACKET expr AS data_type RR_BRACKET
     ;
 
+cast_expr
+    : CAST LR_BRACKET expr AS data_type RR_BRACKET
+    ;
+
 json_literal
     : LCB kv_pair (COMMA kv_pair)* RCB
     | LCB RCB

sql/snowflake/examples/select.sql

@@ -16,6 +16,7 @@ SELECT IFNULL(DATEADD(DAY, -1, CAST(ColDate as date)), CAST('2999-12-31' as date
 SELECT RES FROM (SELECT LEFT('COL1',1) AS RES UNION SELECT RIGHT('COL1',1)) as TableRes;
 SELECT to_date(select dateadd(d,-((date_part(dw,getdate())+1)%7+1),getdate())) AS Res;
 SELECT TRY_CAST("150" as INT);
+SELECT CAST("150" as INT);
 SELECT LEN(COL1), LENGTH (COL2) from t;
 SELECT REPLACE('abcd', 'bc'), CHARINDEX('abcd','c') F;
 SELECT * FROM (SELECT 1 as col1 ,'FuturCol2' as col2 union SELECT 2,'FuturCol3') PIVOT (sum(col1) FOR col2 in ('FuturCol2','FuturCol3'));