Fixed transaction handling for snowflake (#2263)

Author: romanoff

src/dialect/snowflake.rs

@@ -247,6 +247,17 @@ impl Dialect for SnowflakeDialect {
 
     fn parse_statement(&self, parser: &mut Parser) -> Option<Result<Statement, ParserError>> {
         if parser.parse_keyword(Keyword::BEGIN) {
+            // Snowflake supports both `BEGIN TRANSACTION` and `BEGIN ... END` blocks.
+            // If the next keyword indicates a transaction statement, let the
+            // standard parse_begin() handle it.
+            if parser
+                .peek_one_of_keywords(&[Keyword::TRANSACTION, Keyword::WORK, Keyword::NAME])
+                .is_some()
+                || matches!(parser.peek_token_ref().token, Token::SemiColon | Token::EOF)
+            {
+                parser.prev_token();
+                return None;
+            }
             return Some(parser.parse_begin_exception_end());
         }
 

tests/sqlparser_snowflake.rs

@@ -4610,6 +4610,27 @@ END
     assert_eq!(2, exception[1].statements.len());
 }
 
+#[test]
+fn test_begin_transaction() {
+    snowflake().verified_stmt("BEGIN TRANSACTION");
+    snowflake().verified_stmt("BEGIN WORK");
+
+    // BEGIN TRANSACTION with statements
+    let stmts = snowflake()
+        .parse_sql_statements("BEGIN TRANSACTION; DROP TABLE IF EXISTS bla; COMMIT")
+        .unwrap();
+    assert_eq!(3, stmts.len());
+
+    // Bare BEGIN (no TRANSACTION keyword) with statements
+    let stmts = snowflake()
+        .parse_sql_statements("BEGIN; DROP TABLE IF EXISTS bla; COMMIT")
+        .unwrap();
+    assert_eq!(3, stmts.len());
+
+    // Bare BEGIN at EOF (no semicolon, no TRANSACTION keyword)
+    snowflake().verified_stmt("BEGIN");
+}
+
 #[test]
 fn test_snowflake_fetch_clause_syntax() {
     let canonical = "SELECT c1 FROM fetch_test FETCH FIRST 2 ROWS ONLY";