sqlc可以根据我们编写的 SQL 语句生成类型安全的、地道的 Go 接口代码，我们要做的只是调用这些方法。但是sqlc 不支持in 语法，写代码比较痛苦，所以对sqlc进行了修改，添加了in语法支持的功能。

项目地址：

源码：https://github.com/xiazemin/sqlc

实例：https://github.com/xiazemin/sqlc_study

安装

go get -u github.com/xiazemin/sqlc

使用

https://github.com/kyleconroy/sqlc 的sql 是没法解析in操作的

本文实现的sqlc 支持复杂的in 操作比如

– name: GetOneAuthor :one
SELECT * FROM authors where id in (?) and bio=? and name in (?) limit 1;

生成的相关代码如下

const getOneAuthor = -- name: GetOneAuthor :one
SELECT id, name, bio FROM authors where id in (?) and bio=? and name in (?) limit 1


type GetOneAuthorParams struct {
ID []int32

Bio sql.NullString

Name []string
}

func stringSlice2interface(l []string) []interface{} {
v := make([]interface{}, len(l))
for i, val := range l {
v[i] = val

}
return v
}

func (q *Queries) GetOneAuthor(ctx context.Context, arg GetOneAuthorParams) (Author, error) {

getOneAuthor := getOneAuthor

{
param := “?”
for i := 0; i < len(arg.ID)-1; i++ {
param += “,?”
}
getOneAuthor = replaceNth(getOneAuthor, “(?)”, “(“+param+”)”, 1)
}

{
param := “?”
for i := 0; i < len(arg.Name)-1; i++ {
param += “,?”
}
getOneAuthor = replaceNth(getOneAuthor, “(?)”, “(“+param+”)”, 1)
}

row := q.db.QueryRowContext(ctx, getOneAuthor, append(append(int32Slice2interface(arg.ID), arg.Bio), stringSlice2interface(arg.Name)…)…)
var i Author
err := row.Scan(&i.ID, &i.Name, &i.Bio)
return i, err
}
完全兼容以前的sqlc，一键生成支持in 语法的代码，不用手动维护

对子查询类似

https://github.com/pingcap/parser

https://github.com/pingcap/parser/blob/master/parser.y
https://github.com/pingcap/parser/blob/master/docs/quickstart.md