記一次MyBatisPlus問題(如果表名是數據庫關鍵字怎么辦)

問題信息:
如果表名是數據庫關鍵字怎么辦？

正常來說，如果是我們自己寫sql的話，給表名加反引號即可解決問題。

但是由於我們使用MyBatisPlus，相關的sql基本上都是封裝並自動生成的。如果是這種場景，我們就需要修改對應的實體，舉例說明，如下代碼:

import com.baomidou.mybatisplus.enums.IdType;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.activerecord.Model;
import java.io.Serializable;

public class Group extends Model<Group> {

    private static final long serialVersionUID = 1L;

    /**
     * 組ID
     */
    @TableId(value = "id", type = IdType.AUTO)
    private Integer id;
    /**
     * 組名
     */
    private String name;


    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    protected Serializable pkVal() {
        return this.id;
    }

    @Override
    public String toString() {
        return "Group{" +
        "id=" + id +
        ", name=" + name +
        "}";
    }
}

用上述代碼的自動生成肯定會有問題，以單條數據查詢為例，默認是 select id,name from group where id = 1，又因為group屬於關鍵字，接下來會出現如下錯誤信息:

### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'group WHERE id=1' at line 1
; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'group WHERE id=1' at line 1] with root cause

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'group WHERE id=1' at line 1

這種錯誤信息，很容易識別，一看就是sql寫的有問題。但實際上sql並沒有問題，只不過是因為關鍵字沖突導致sql錯誤。

那么如何解決這個問題呢？
答案是只需加一個@TableName注解即可解決該問題。修改后的實體代碼如下:

import com.baomidou.mybatisplus.enums.IdType;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.annotations.TableName;
import com.baomidou.mybatisplus.activerecord.Model;
import java.io.Serializable;


@TableName("`group`")
public class Group extends Model<Group> {

    private static final long serialVersionUID = 1L;

    /**
     * 組ID
     */
    @TableId(value = "id", type = IdType.AUTO)
    private Integer id;
    /**
     * 組名
     */
    private String name;


    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    protected Serializable pkVal() {
        return this.id;
    }

    @Override
    public String toString() {
        return "Group{" +
        "id=" + id +
        ", name=" + name +
        "}";
    }
}