mybatis中dual
时间: 2023-11-17 21:07:31 浏览: 47
MyBatis does not have an equivalent feature like Oracle's `DUAL` table. The `DUAL` table in Oracle is a dummy table used to perform calculations or perform queries without actually querying a real table.
In MyBatis, you can execute simple queries without using a specific table by using inline queries or by executing a dummy query against any existing table. For example, you can use the following inline query to select a single value without accessing a specific table:
```xml
<select id="selectDummy" resultType="java.lang.String">
SELECT #{dummyValue} AS DUMMY FROM DUAL
</select>
```
In this example, `dummyValue` is a parameter that you can pass to the query to get a dummy result.
Alternatively, you can also execute a query against any existing table in your database, even if it does not contain the data you need. This way, you can achieve similar functionality to the `DUAL` table in Oracle.
I hope this helps! Let me know if you have any further questions.
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