improved mysql parser.

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlReplaceStatement.java

@@ -90,7 +90,9 @@ public class MySqlReplaceStatement extends MySqlStatementImpl {
     }
 
     public void setQuery(SQLQueryExpr query) {
-        query.setParent(this);
+        if (query != null) {
+            query.setParent(this);
+        }
         this.query = query;
     }
 

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlStatementParser.java

@@ -1850,10 +1850,9 @@ public class MySqlStatementParser extends SQLStatementParser {
                 break;
             }
         } else if (lexer.token() == Token.LPAREN) {
-            lexer.nextToken();
-            SQLQueryExpr queryExpr = (SQLQueryExpr) this.exprParser.expr();
+            SQLSelect select = this.createSQLSelectParser().select();
+            SQLQueryExpr queryExpr = new SQLQueryExpr(select);
             stmt.setQuery(queryExpr);
-            accept(Token.RPAREN);
         }
 
         return stmt;

src/main/java/com/alibaba/druid/sql/parser/SQLParser.java

@@ -240,6 +240,7 @@ public class SQLParser {
                 case ADVISE:
                 case TYPE:
                 case CLOSE:
+                case OPEN:
                     alias = lexer.stringVal();
                     lexer.nextToken();
                     return alias;