feat:多租户插件的查询使用索引的优化#6687

mybatis-plus-jsqlparser-support/mybatis-plus-jsqlparser/src/main/java/com/baomidou/mybatisplus/extension/plugins/handler/TenantLineHandler.java

@@ -47,6 +47,18 @@ default String getTenantIdColumn() {
         return "tenant_id";
     }
 
+    /**
+     * where语句租户字段名是否前置
+     * <p>
+     * 默认为不前置 where id=? and name=? and tenant_id=?
+     * 前置，可以使用索引 where tenant_id=? and id=? and name=?
+     *
+     * @return 是否前置
+     */
+    default boolean tenantIdColumnFirst() {
+        return false;
+    }
+
     /**
      * 根据表名判断是否忽略拼接多租户条件
      * <p>

mybatis-plus-jsqlparser-support/mybatis-plus-jsqlparser/src/main/java/com/baomidou/mybatisplus/extension/plugins/inner/TenantLineInnerInterceptor.java

@@ -21,6 +21,8 @@
 import com.baomidou.mybatisplus.extension.toolkit.PropertyMapper;
 import lombok.*;
 import net.sf.jsqlparser.expression.Expression;
+import net.sf.jsqlparser.expression.operators.conditional.AndExpression;
+import net.sf.jsqlparser.expression.operators.conditional.OrExpression;
 import net.sf.jsqlparser.expression.operators.relational.EqualsTo;
 import net.sf.jsqlparser.expression.operators.relational.ExpressionList;
 import net.sf.jsqlparser.expression.operators.relational.ParenthesedExpressionList;
@@ -261,4 +263,16 @@ public Expression buildTableExpression(final Table table, final Expression where
         }
         return new EqualsTo(getAliasColumn(table), tenantLineHandler.getTenantId());
     }
+
+    @Override
+    public Expression builderExpression(Expression currentExpression, List<Table> tables, final String whereSegment) {
+        Expression expression = super.builderExpression(currentExpression, tables, whereSegment);
+        if (tenantLineHandler.tenantIdColumnFirst() && expression instanceof AndExpression) {
+            AndExpression andExpression = (AndExpression) expression;
+            Expression leftExpression = andExpression.getLeftExpression();
+            andExpression.setLeftExpression(andExpression.getRightExpression());
+            andExpression.setRightExpression(leftExpression);
+        }
+        return expression;
+    }
 }

mybatis-plus-jsqlparser-support/mybatis-plus-jsqlparser/src/test/java/com/baomidou/mybatisplus/test/extension/plugins/inner/TenantLineInnerInterceptorTest.java

@@ -13,6 +13,7 @@
  * @since 2020-07-30
  */
 class TenantLineInnerInterceptorTest {
+    private boolean tenantIdColumnFirst = false;
 
     private final TenantLineInnerInterceptor interceptor = new TenantLineInnerInterceptor(new TenantLineHandler() {
         private boolean ignoreFirst;// 需要执行 getTenantId 前必须先执行 ignoreTable
@@ -29,6 +30,11 @@ public boolean ignoreTable(String tableName) {
             ignoreFirst = true;
             return tableName.startsWith("with_as");
         }
+
+        @Override
+        public boolean tenantIdColumnFirst() {
+            return tenantIdColumnFirst;
+        }
     });
 
     @Test
@@ -109,6 +115,28 @@ void selectSingle() {
             "SELECT * FROM entity u WHERE NOT (u.id = ? OR u.name = ?) AND u.tenant_id = 1");
     }
 
+    @Test
+    void selectSingleTenantIdColumnFirst() {
+        tenantIdColumnFirst = true;
+        // 单表
+        assertSql("select * from entity where id = ?",
+            "SELECT * FROM entity WHERE tenant_id = 1 AND id = ?");
+
+        assertSql("select * from entity where id = ? or name = ?",
+            "SELECT * FROM entity WHERE tenant_id = 1 AND (id = ? OR name = ?)");
+
+        assertSql("SELECT * FROM entity WHERE (id = ? OR name = ?)",
+            "SELECT * FROM entity WHERE tenant_id = 1 AND (id = ? OR name = ?)");
+
+        /* not */
+        assertSql("SELECT * FROM entity WHERE not (id = ? OR name = ?)",
+            "SELECT * FROM entity WHERE tenant_id = 1 AND NOT (id = ? OR name = ?)");
+
+        assertSql("SELECT * FROM entity u WHERE not (u.id = ? OR u.name = ?)",
+            "SELECT * FROM entity u WHERE u.tenant_id = 1 AND NOT (u.id = ? OR u.name = ?)");
+        tenantIdColumnFirst = false;
+    }
+
     @Test
     void selectSubSelectIn() {
         /* in */