improved sql parser.

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

@@ -40,7 +40,7 @@ public class MySqlShowColumnOutpuVisitor extends MySqlOutputVisitor {
         List<String> dataTypes = new ArrayList<String>();
         List<String> defaultValues = new ArrayList<String>();
 
-        int name_len = -1, dataType_len = -1, defaultVal_len = -1, extra_len = 5;
+        int name_len = -1, dataType_len = -1, defaultVal_len = 7, extra_len = 5;
         for (SQLTableElement element : x.getTableElementList()) {
             if (element instanceof SQLColumnDefinition) {
                 SQLColumnDefinition column = (SQLColumnDefinition) element;

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OraclePrimaryKey.java

@@ -60,10 +60,6 @@ public class OraclePrimaryKey extends SQLPrimaryKeyImpl implements OracleConstra
         this.deferrable = deferrable;
     }
 
-    public List<SQLExpr> getColumns() {
-        return columns;
-    }
-
     public OracleUsingIndexClause getUsing() {
         return using;
     }

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

@@ -1019,7 +1019,7 @@ public class OracleExprParser extends SQLExprParser {
 
         OraclePrimaryKey primaryKey = new OraclePrimaryKey();
         accept(Token.LPAREN);
-        exprList(primaryKey.getColumns(), primaryKey);
+        orderBy(primaryKey.getColumns(), primaryKey);
         accept(Token.RPAREN);
 
         
@@ -1349,7 +1349,7 @@ public class OracleExprParser extends SQLExprParser {
 
         OracleUnique unique = new OracleUnique();
         accept(Token.LPAREN);
-        exprList(unique.getColumns(), unique);
+        orderBy(unique.getColumns(), unique);
         accept(Token.RPAREN);
         
         if (lexer.token() == Token.USING) {