mysql parser support Hierarchical clause.

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

@@ -158,6 +158,8 @@ public class MySqlSelectParser extends SQLSelectParser {
 
         parseWhere(queryBlock);
 
+        parseHierachical(queryBlock);
+
         parseGroupBy(queryBlock);
 
         queryBlock.setOrderBy(this.exprParser.parseOrderBy());

src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java

@@ -279,6 +279,8 @@ public class MySqlOutputVisitor extends SQLASTOutputVisitor implements MySqlASTV
             x.getWhere().accept(this);
         }
 
+        printHierarchical(x);
+
         if (x.getGroupBy() != null) {
             println();
             x.getGroupBy().accept(this);

src/main/java/com/alibaba/druid/sql/dialect/odps/parser/OdpsSelectParser.java

@@ -148,7 +148,7 @@ public class OdpsSelectParser extends SQLSelectParser {
                 break;
             }
 
-            String alias = this.as();
+            String alias = this.tableAlias();
             tableSource.setAlias(alias);
 
             accept(Token.LPAREN);

src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleSelectParser.java

@@ -563,66 +563,9 @@ public class OracleSelectParser extends SQLSelectParser {
     }
 
     protected String as() {
-        if (lexer.token() == Token.CONNECT) {
-            return null;
-        }
-
         return super.as();
     }
 
-    private void parseHierachical(OracleSelectQueryBlock queryBlock) {
-
-
-        if (lexer.token() == Token.CONNECT) {
-            lexer.nextToken();
-            accept(Token.BY);
-
-            if (lexer.token() == Token.PRIOR) {
-                lexer.nextToken();
-                queryBlock.setPrior(true);
-            }
-
-            if (identifierEquals("NOCYCLE")) {
-                queryBlock.setNoCycle(true);
-                lexer.nextToken();
-
-                if (lexer.token() == Token.PRIOR) {
-                    lexer.nextToken();
-                    queryBlock.setPrior(true);
-                }
-            }
-            queryBlock.setConnectBy(this.exprParser.expr());
-        }
-
-        if (lexer.token() == Token.START) {
-            lexer.nextToken();
-            accept(Token.WITH);
-
-            queryBlock.setStartWith(this.exprParser.expr());
-        }
-
-        if (lexer.token() == Token.CONNECT) {
-            lexer.nextToken();
-            accept(Token.BY);
-
-            if (lexer.token() == Token.PRIOR) {
-                lexer.nextToken();
-                queryBlock.setPrior(true);
-            }
-
-            if (identifierEquals("NOCYCLE")) {
-                queryBlock.setNoCycle(true);
-                lexer.nextToken();
-
-                if (lexer.token() == Token.PRIOR) {
-                    lexer.nextToken();
-                    queryBlock.setPrior(true);
-                }
-            }
-            queryBlock.setConnectBy(this.exprParser.expr());
-        }
-    }
-
     @Override
     public SQLTableSource parseTableSource() {
         if (lexer.token() == (Token.LPAREN)) {
@@ -807,10 +750,10 @@ public class OracleSelectParser extends SQLSelectParser {
                 tableSource.setFlashback(flashback());
             }
 
-            tableSource.setAlias(as());
+            tableSource.setAlias(tableAlias());
         } else if ((tableSource.getAlias() == null) || (tableSource.getAlias().length() == 0)) {
             if (lexer.token() != Token.LEFT && lexer.token() != Token.RIGHT && lexer.token() != Token.FULL) {
-                tableSource.setAlias(as());
+                tableSource.setAlias(tableAlias());
             }
         }
 

src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleStatementParser.java

@@ -1273,7 +1273,7 @@ public class OracleStatementParser extends SQLStatementParser {
                 deleteStatement.setTableName(tableName);
             }
 
-            deleteStatement.setAlias(as());
+            deleteStatement.setAlias(tableAlias());
         }
 
         if (lexer.token() == (Token.WHERE)) {

src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleUpdateParser.java

@@ -49,7 +49,7 @@ public class OracleUpdateParser extends SQLStatementParser {
             update.setTableSource(tableSource);
 
             if ((update.getAlias() == null) || (update.getAlias().length() == 0)) {
-                update.setAlias(as());
+                update.setAlias(tableAlias());
             }
         }
 

src/main/java/com/alibaba/druid/sql/dialect/oracle/visitor/OracleOutputVisitor.java

@@ -527,27 +527,7 @@ public class OracleOutputVisitor extends SQLASTOutputVisitor implements OracleAS
             x.getWhere().accept(this);
         }
 
-        SQLExpr startWith = x.getStartWith(), connectBy = x.getConnectBy();
-        if (startWith != null || connectBy != null){
-            println();
-            if (x.getStartWith() != null) {
-                print0(ucase ? "START WITH " : "start with ");
-                x.getStartWith().accept(this);
-                println();
-            }
-
-            print0(ucase ? "CONNECT BY " : "connect by ");
-
-            if (x.isNoCycle()) {
-                print0(ucase ? "NOCYCLE " : "nocycle ");
-            }
-
-            if (x.isPrior()) {
-                print0(ucase ? "PRIOR " : "prior ");
-            }
-
-            x.getConnectBy().accept(this);
-        }
+        printHierarchical(x);
 
         if (x.getGroupBy() != null) {
             println();

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerStatementParser.java

@@ -256,7 +256,7 @@ public class SQLServerStatementParser extends SQLStatementParser {
         insertStatement.setTableName(tableName);
 
         if (lexer.token() == Token.LITERAL_ALIAS) {
-            insertStatement.setAlias(as());
+            insertStatement.setAlias(tableAlias());
         }
 
         parseInsert0_hinits(insertStatement);