分库分表：结果集处理——聚合函数（不含 Group By 子句)

[juniaoshaonian]

No description provided.

[codecov]

Codecov Report

Merging #187 (25ff222) into dev (96d0b3c) will increase coverage by 1.20%.
The diff coverage is 96.27%.

@@            Coverage Diff             @@
##              dev     #187      +/-   ##
==========================================
+ Coverage   84.86%   86.07%   +1.20%     
==========================================
  Files          36       43       +7     
  Lines        2723     3045     +322     
==========================================
+ Hits         2311     2621     +310     
- Misses        335      343       +8     
- Partials       77       81       +4     

Impacted Files	Coverage Δ
internal/merger/aggregatemerger/merger.go	92.15% <92.15%> (ø)
internal/merger/aggregatemerger/aggregator/avg.go	100.00% <100.00%> (ø)
...nternal/merger/aggregatemerger/aggregator/count.go	100.00% <100.00%> (ø)
internal/merger/aggregatemerger/aggregator/max.go	100.00% <100.00%> (ø)
internal/merger/aggregatemerger/aggregator/min.go	100.00% <100.00%> (ø)
internal/merger/aggregatemerger/aggregator/sum.go	100.00% <100.00%> (ø)
internal/merger/aggregatemerger/aggregator/type.go	100.00% <100.00%> (ø)

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[flycash]

明日再看看

[flycash]

func TestColumnType(t *testing.T) {
	db, err := sql.Open("mysql", "root:root@tcp(localhost:13306)/integration_test")
	require.NoError(t, err)
	defer func() {
		db.Exec("DELETE FROM `order`")
		db.Exec("DELETE FROM `item`")
		db.Exec("DELETE FROM `order_detail`")
	}()
	o, err := eorm.Open("mysql", single.NewDB(db))
	require.NoError(t, err)
	initSql(o, t)
	rows, err := db.Query("SELECT * FROM `order` limit 1")
	require.NoError(t, err)
	types, err := rows.ColumnTypes()
	require.NoError(t, err)
	var vals []any
	for _, typ := range types {
		goType := typ.ScanType()
		zero := reflect.New(goType)
		vals = append(vals, zero.Interface())
	}
	rows.Next()
	err = rows.Scan(vals...)
	require.NoError(t, err)
	fmt.Println(vals)
}

确实可以拿到。但是我没有进一步考察，还要考虑一些数据库上奇怪的类型，尤其是 big int, big unsign int 之类的，在转为 Go 类型的时候会不会有问题。

[flycash]

我注意到一个问题，在除了 Avg 以外的所有的聚合函数都要求传入一个 alias，我看上去有点多余。比如说在 ColInfo 里面已经有了一个 name，那么在我的设想里面，这个 name 代表的就是我们的列名，即是数据库返回的列名，也是我们在 rows.Columns 里面使用的列名。

那么：

SELECT SUM(age) FROM

ColInfo.name 应该是 SUM(age)
而：

SELECT SUM(age) as sum_age FROM

这个 ColInfo.Name 就是 sum_age。

在结果集处理层面上，应该没有 alias 这个概念的。

[flycash]

@juniaoshaonian deepsource 有一个小问题，你修复一下。
@longyue0521 确认没有问题之后你就可以合并了。

[longyue0521]

确认没有问题之后你就可以合并了。

OK

[Stone-afk]

mark

[longyue0521]

@juniaoshaonian golangci-lint 问题修复一下

[juniaoshaonian]

@juniaoshaonian golangci-lint 问题修复一下

奇怪了我就改了个变量名呀，昨天还可以的