fix oci batchInsert

default batchInsert sql is
```
insert into  tableName(col1, col2, col3...) value(`col11`, `col12`,`col13`.... ),(`col21`, `col22`,`col23`.... );
```
which is illegal in oracle db. Change it to
```
insert into tableName(col1, col2, col3...)
  select 'col11', 'col12', 'col13' from dual union
  select 'col21', 'col22', 'col23' from dual union
  select 'col31', 'col32', 'col33' from dual;
```