javascript - 我想要 Sequelize 形式的这个查询

Question

我在 RAW SQL 中获得输出，但我无法使用 SequelizeJS

SELECT * FROM `tbl_a` a 
LEFT JOIN `tbl_b` b on b.b_uuid = a.a_uuid
LEFT JOIN `tbl_c` c on c.c_uuid = a.a_uuid

Answer 1

我假设这些表的关系是这样的:

tbl_a 和 tbl_b :一对一关系

tbl_a 和 tbl_c :一对一关系

Sequelize 版本: "sequelize": "^5.21.3"

/* eslint-disable @typescript-eslint/camelcase */
import { sequelize } from '../../db';
import { Model, DataTypes } from 'sequelize';

class TblA extends Model {}
TblA.init(
  {
    a_uuid: {
      type: DataTypes.UUID,
      defaultValue: DataTypes.UUIDV4,
      primaryKey: true,
    },
  },
  { sequelize, modelName: 'tbl_a' },
);

class TblB extends Model {}
TblB.init(
  {
    b_uuid: {
      type: DataTypes.UUID,
      defaultValue: DataTypes.UUIDV4,
    },
  },
  { sequelize, modelName: 'tbl_b' },
);

class TblC extends Model {}
TblC.init(
  {
    c_uuid: {
      type: DataTypes.UUID,
      defaultValue: DataTypes.UUIDV4,
    },
  },
  { sequelize, modelName: 'tbl_c' },
);

TblA.hasOne(TblB, { foreignKey: 'b_uuid', sourceKey: 'a_uuid', as: 'b' });
TblB.belongsTo(TblA, { foreignKey: 'b_uuid', targetKey: 'a_uuid' });

TblA.hasOne(TblC, { foreignKey: 'c_uuid', sourceKey: 'a_uuid', as: 'c' });
TblC.belongsTo(TblA, { foreignKey: 'c_uuid', targetKey: 'a_uuid' });

(async function test() {
  try {
    await sequelize.sync({ force: true });
    // seed
    await TblA.create(
      {
        b: {},
        c: {},
      },
      {
        include: [
          { model: TblB, as: 'b' },
          { model: TblC, as: 'c' },
        ],
      },
    );

    // test
    const result = await TblA.findAll({
      include: [
        { model: TblB, as: 'b', required: false },
        { model: TblC, as: 'c', required: false },
      ],
      raw: true,
    });
    console.log(result);
  } catch (error) {
    console.log(error);
  } finally {
    await sequelize.close();
  }
})();

执行结果:

Executing (default): DROP TABLE IF EXISTS "tbl_c" CASCADE;
Executing (default): DROP TABLE IF EXISTS "tbl_b" CASCADE;
Executing (default): DROP TABLE IF EXISTS "tbl_a" CASCADE;
Executing (default): DROP TABLE IF EXISTS "tbl_a" CASCADE;
Executing (default): CREATE TABLE IF NOT EXISTS "tbl_a" ("a_uuid" UUID , PRIMARY KEY ("a_uuid"));
Executing (default): SELECT i.relname AS name, ix.indisprimary AS primary, ix.indisunique AS unique, ix.indkey AS indkey, array_agg(a.attnum) as column_indexes, array_agg(a.attname) AS column_names, pg_get_indexdef(ix.indexrelid) AS definition FROM pg_class t, pg_class i, pg_index ix, pg_attribute a WHERE t.oid = ix.indrelid AND i.oid = ix.indexrelid AND a.attrelid = t.oid AND t.relkind = 'r' and t.relname = 'tbl_a' GROUP BY i.relname, ix.indexrelid, ix.indisprimary, ix.indisunique, ix.indkey ORDER BY i.relname;
Executing (default): DROP TABLE IF EXISTS "tbl_b" CASCADE;
Executing (default): CREATE TABLE IF NOT EXISTS "tbl_b" ("id"   SERIAL , "b_uuid" UUID REFERENCES "tbl_a" ("a_uuid") ON DELETE CASCADE ON UPDATE CASCADE, PRIMARY KEY ("id"));
Executing (default): SELECT i.relname AS name, ix.indisprimary AS primary, ix.indisunique AS unique, ix.indkey AS indkey, array_agg(a.attnum) as column_indexes, array_agg(a.attname) AS column_names, pg_get_indexdef(ix.indexrelid) AS definition FROM pg_class t, pg_class i, pg_index ix, pg_attribute a WHERE t.oid = ix.indrelid AND i.oid = ix.indexrelid AND a.attrelid = t.oid AND t.relkind = 'r' and t.relname = 'tbl_b' GROUP BY i.relname, ix.indexrelid, ix.indisprimary, ix.indisunique, ix.indkey ORDER BY i.relname;
Executing (default): DROP TABLE IF EXISTS "tbl_c" CASCADE;
Executing (default): CREATE TABLE IF NOT EXISTS "tbl_c" ("id"   SERIAL , "c_uuid" UUID REFERENCES "tbl_a" ("a_uuid") ON DELETE CASCADE ON UPDATE CASCADE, PRIMARY KEY ("id"));
Executing (default): SELECT i.relname AS name, ix.indisprimary AS primary, ix.indisunique AS unique, ix.indkey AS indkey, array_agg(a.attnum) as column_indexes, array_agg(a.attname) AS column_names, pg_get_indexdef(ix.indexrelid) AS definition FROM pg_class t, pg_class i, pg_index ix, pg_attribute a WHERE t.oid = ix.indrelid AND i.oid = ix.indexrelid AND a.attrelid = t.oid AND t.relkind = 'r' and t.relname = 'tbl_c' GROUP BY i.relname, ix.indexrelid, ix.indisprimary, ix.indisunique, ix.indkey ORDER BY i.relname;
Executing (default): INSERT INTO "tbl_a" ("a_uuid") VALUES ($1) RETURNING *;
Executing (default): INSERT INTO "tbl_b" ("id","b_uuid") VALUES (DEFAULT,$1) RETURNING *;
Executing (default): INSERT INTO "tbl_c" ("id","c_uuid") VALUES (DEFAULT,$1) RETURNING *;
Executing (default): SELECT "tbl_a"."a_uuid", "b"."id" AS "b.id", "b"."b_uuid" AS "b.b_uuid", "c"."id" AS "c.id", "c"."c_uuid" AS "c.c_uuid" FROM "tbl_a" AS "tbl_a" LEFT OUTER JOIN "tbl_b" AS "b" ON "tbl_a"."a_uuid" = "b"."b_uuid" LEFT OUTER JOIN "tbl_c" AS "c" ON "tbl_a"."a_uuid" = "c"."c_uuid";
[ { a_uuid: '1c9cf677-baa9-48c8-ac9b-3e617980c046',
    'b.id': 1,
    'b.b_uuid': '1c9cf677-baa9-48c8-ac9b-3e617980c046',
    'c.id': 1,
    'c.c_uuid': '1c9cf677-baa9-48c8-ac9b-3e617980c046' } ]

sequelize生成的SQL为:

SELECT 
  "tbl_a"."a_uuid", 
  "b"."id" AS "b.id", 
  "b"."b_uuid" AS "b.b_uuid", 
  "c"."id" AS "c.id", 
  "c"."c_uuid" AS "c.c_uuid" 
FROM "tbl_a" AS "tbl_a" 
LEFT OUTER JOIN "tbl_b" AS "b" ON "tbl_a"."a_uuid" = "b"."b_uuid" 
LEFT OUTER JOIN "tbl_c" AS "c" ON "tbl_a"."a_uuid" = "c"."c_uuid";

数据库中的数据记录:

node-sequelize-examples=# select * from tbl_a;
                a_uuid
--------------------------------------
 9d982af2-0ee6-407e-93ee-d9d404178756
(1 row)

node-sequelize-examples=# select * from tbl_b;
 id |                b_uuid
----+--------------------------------------
  1 | 9d982af2-0ee6-407e-93ee-d9d404178756
(1 row)

node-sequelize-examples=# select * from tbl_c;
 id |                c_uuid
----+--------------------------------------
  1 | 9d982af2-0ee6-407e-93ee-d9d404178756
(1 row)