mysql parser refactor.

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

@@ -190,6 +190,8 @@ public class Lexer {
         int   sp;
         int   np;
         char  ch;
+        long hash;
+        long hash_lower;
         Token token;
         String stringVal;
     }
@@ -206,6 +208,8 @@ public class Lexer {
         savePoint.ch = ch;
         savePoint.token = token;
         savePoint.stringVal = stringVal;
+        savePoint.hash = hash;
+        savePoint.hash_lower = hash_lower;
         return this.savePoint = savePoint;
     }
 
@@ -216,6 +220,8 @@ public class Lexer {
         this.ch = savePoint.ch;
         this.token = savePoint.token;
         this.stringVal = savePoint.stringVal;
+        this.hash = savePoint.hash;
+        this.hash_lower = savePoint.hash_lower;
     }
 
     public void reset() {

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

@@ -21,6 +21,7 @@ import com.alibaba.druid.sql.ast.*;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.statement.*;
 import com.alibaba.druid.sql.dialect.mysql.ast.expr.MySqlOrderingExpr;
+import com.alibaba.druid.sql.dialect.oracle.ast.stmt.OracleSelectQueryBlock;
 import com.alibaba.druid.util.FNVUtils;
 import com.alibaba.druid.util.JdbcConstants;
 
@@ -48,11 +49,25 @@ public class SQLSelectParser extends SQLParser {
             select.setWithSubQuery(with);
         }
 
-        select.setQuery(query());
-        select.setOrderBy(parseOrderBy());
+        SQLSelectQuery query = query();
+        select.setQuery(query);
 
-        if (select.getOrderBy() == null) {
-            select.setOrderBy(parseOrderBy());
+        SQLOrderBy orderBy = this.parseOrderBy();
+
+        if (query instanceof SQLSelectQueryBlock) {
+            SQLSelectQueryBlock queryBlock = (SQLSelectQueryBlock) query;
+
+            if (queryBlock.getOrderBy() == null) {
+                queryBlock.setOrderBy(orderBy);
+            } else {
+                select.setOrderBy(orderBy);
+            }
+
+            if (orderBy != null) {
+                parseFetchClause(queryBlock);
+            }
+        } else {
+            select.setOrderBy(orderBy);
         }
 
         while (lexer.token == Token.HINT) {
@@ -609,17 +624,20 @@ public class SQLSelectParser extends SQLParser {
                 rightTableSource = new SQLExprTableSource(expr);
             }
 
-            if (lexer.identifierEquals("USING")) {
+            if (lexer.token == Token.USING
+                ||lexer.identifierEquals(FNVUtils.USING))
+            {
+                Lexer.SavePoint savePoint = lexer.mark();
                 lexer.nextToken();
-                if (lexer.token == Token.LPAREN) {
-                    lexer.nextToken();
-                    this.exprParser.exprList(join.getUsing(), join);
-                    accept(Token.RPAREN);
-                } else {
-                    join.getUsing().add(this.expr());
-                }
 
-                join.setAlias(this.tableAlias());
+                if (lexer.token == Token.LPAREN
+                        || lexer.token == Token.IDENTIFIER) {
+                    lexer.reset(savePoint);
+                    join.setRight(rightTableSource);
+                    return join;
+                } else {
+                    join.setAlias(this.tableAlias());
+                }
             } else {
                 rightTableSource.setAlias(this.tableAlias());
 
@@ -659,14 +677,16 @@ public class SQLSelectParser extends SQLParser {
             if (lexer.token == Token.ON) {
                 lexer.nextToken();
                 join.setCondition(expr());
-            } else if (lexer.identifierEquals("USING")) {
+            } else if (lexer.token == Token.USING
+                    || lexer.identifierEquals(FNVUtils.USING)) {
+                Lexer.SavePoint savePoint = lexer.mark();
                 lexer.nextToken();
                 if (lexer.token == Token.LPAREN) {
                     lexer.nextToken();
                     this.exprParser.exprList(join.getUsing(), join);
                     accept(Token.RPAREN);
                 } else {
-                    join.getUsing().add(this.expr());
+                    lexer.reset(savePoint);
                 }
             }
 

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

@@ -369,7 +369,15 @@ public class SQLStatementParser extends SQLParser {
                 }
             }
 
+            int size = statementList.size();
             if (parseStatementListDialect(statementList)) {
+                if (parent != null) {
+                    for (int i = size; i < statementList.size(); ++i) {
+                        SQLStatement dialectStmt = statementList.get(i);
+                        dialectStmt.setParent(parent);
+                    }
+                }
+
                 continue;
             }
 
@@ -2593,6 +2601,7 @@ public class SQLStatementParser extends SQLParser {
         accept(Token.MERGE);
 
         SQLMergeStatement stmt = new SQLMergeStatement();
+        stmt.setDbType(dbType);
 
         parseHints(stmt.getHints());
 
@@ -2608,7 +2617,7 @@ public class SQLStatementParser extends SQLParser {
             stmt.setInto(exprParser.name());
         }
         
-        stmt.setAlias(tableAlias());
+        stmt.getInto().setAlias(tableAlias());
 
         accept(Token.USING);