_(注意:我使用的是 Postgres;这可能不适用于其他方言)_
我有一个查询,它返回一个平均分数,以及通过的人数,一个测验。 这是我正在尝试做的简化版本:
knex( 'quiz_submissions AS qs' )
.select( 'q.name AS quiz_name' )
.avg( 'qs.score' )
.sum( '(case when qs.score >= 60 then 1 else 0 end) AS passedCount' )
.innerJoin( 'quizzes AS q', 'q.id', 'qs.quiz_id' )
.groupBy( 'q.name' );
(注意sum
)
不幸的是,这并没有像我预期的那样呈现SUM
函数:
sum("(case when qs"."score >= 60 then 1 else 0 end)") as "passedCount"
sumRaw
函数?如果用knex.raw
将参数包装到sum
$ 是否有效?
看起来不像...如果我将总和更改为:
.sum( knex.raw( '(case when qs.score >= 60 then 1 else 0 end) AS passedCount' ) )
我收到错误“val.toLowerCase 不是函数”
(我试过用parenteses,没有,添加as
别名,把它拿走,每次的错误都是一样的)
堆栈跟踪:
TypeError: val.toLowerCase is not a function
at QueryCompiler_PG.aggregate (../../src/query/compiler.js:166:25)
at QueryCompiler_PG.columns (../../src/query/compiler.js:152:25)
at ../../src/query/compiler.js:82:22
at Array.map (native)
at QueryCompiler_PG.select (../../src/query/compiler.js:81:35)
at QueryCompiler_PG.toSQL (../../src/query/compiler.js:45:5)
at QueryBuilder.toSQL (../../src/query/builder.js:41:49)
at ../src/runner.js:34:7
at tryCatcher (util.js:16:23)
at using.js:185:26
at tryCatcher (util.js:16:23)
at Promise._settlePromiseFromHandler (promise.js:504:31)
at Promise._settlePromise (promise.js:561:18)
at Promise._settlePromise0 (promise.js:606:10)
at Promise._settlePromises (promise.js:685:18)
at Promise._fulfill (promise.js:630:18)
From previous event:
at Promise.longStackTracesCaptureStackTrace [as _captureStackTrace] (debuggability.js:369:19)
at Promise._then (promise.js:230:17)
at Promise.then (promise.js:123:17)
at Function.Promise.using (using.js:169:14)
at Runner.run (../src/runner.js:27:20)
at QueryBuilder.Target.then (../src/interface.js:22:50)
at process._tickCallback (node.js:369:9)
knex 版本是 0.11.7,虽然我升级到 0.11.9 并得到相同的消息。
在#238 中找到了解决方法; 在select
而不是sum
knex.raw
现在我输入它似乎很明显......
knex( 'quiz_submissions AS qs' )
.select( 'q.name AS quiz_name', knex.raw( 'SUM(case when qs.score >= 60 then 1 else 0 end) AS passedCount' ) )
.avg( 'qs.score' )
.innerJoin( 'quizzes AS q', 'q.id', 'qs.quiz_id' )
.groupBy( 'q.name' );
最有用的评论
在#238 中找到了解决方法; 在
select
而不是sum
knex.raw
现在我输入它似乎很明显......