rake jobs:work 给出“PGError: ERROR: SELECT FOR UPDATE/SHARE is not allowed in subqueries”答案

【问题标题】：rake jobs:work gives "PGError: ERROR: SELECT FOR UPDATE/SHARE is not allowed in subqueries"rake jobs:work 给出“PGError: ERROR: SELECT FOR UPDATE/SHARE is not allowed in subqueries”
【发布时间】：2015-08-11 13:59:08
【问题描述】：

我正在合并我的 Rails 应用程序的一些更改，其中包括添加了延迟作业 gem（看起来很棒）。为了测试它，我：

跑rails g delayed_job
运行rake db:migrate，它创建了delayed_jobs 表
重启rails server（以防万一）
重启了postgresql服务（以防万一）
跑scripts/delayed_job start
执行了一些任务来累积延迟的作业

但什么也没发生：/我的作业在延迟作业表中，但 locked_at 为空（last_error 也是如此）。

所以我尝试了rake jobs:work，它给出了一个奇怪的 Postgres 错误：
PGError: ERROR: SELECT FOR UPDATE/SHARE is not allowed in subqueries 和痕迹：

$ rake jobs:work
[Worker(host:robert-vaio pid:21217)] Starting job worker
rake aborted!
PGError: ERROR:  SELECT FOR UPDATE/SHARE is not allowed in subqueries
: UPDATE "delayed_jobs" SET locked_at = '2013-02-13 19:53:46.803085', locked_by = 'host:robert-vaio pid:21217' WHERE id IN (SELECT  id FROM "delayed_jobs"  WHERE ((run_at <= '2013-02-13 19:53:46.792619' AND (locked_at IS NULL OR locked_at < '2013-02-13 15:53:46.792639') OR locked_by = 'host:robert-vaio pid:21217') AND failed_at IS NULL) ORDER BY priority ASC, run_at ASC LIMIT 1 FOR UPDATE) RETURNING *
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:1153:in `async_exec'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:1153:in `exec_no_cache'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:662:in `block in exec_query'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract_adapter.rb:280:in `block in log'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activesupport-3.2.12/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract_adapter.rb:275:in `log'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:661:in `exec_query'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:1248:in `select'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/database_statements.rb:18:in `select_all'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/query_cache.rb:63:in `select_all'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/querying.rb:38:in `block in find_by_sql'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/explain.rb:33:in `logging_query_plan'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/activerecord-3.2.12/lib/active_record/querying.rb:37:in `find_by_sql'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job_active_record-0.4.1/lib/delayed/backend/active_record.rb:63:in `reserve'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:258:in `reserve_and_run_one_job'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:187:in `block in work_off'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:186:in `times'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:186:in `work_off'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:151:in `block (4 levels) in start'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:150:in `block (3 levels) in start'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:60:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:60:in `block in initialize'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:65:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:65:in `execute'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:38:in `run_callbacks'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:149:in `block (2 levels) in start'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:148:in `loop'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:148:in `block in start'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/plugins/clear_locks.rb:7:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/plugins/clear_locks.rb:7:in `block (2 levels) in <class:ClearLocks>'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:78:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:78:in `block (2 levels) in add'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:60:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:60:in `block in initialize'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:78:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:78:in `block in add'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:65:in `call'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:65:in `execute'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/lifecycle.rb:38:in `run_callbacks'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/worker.rb:147:in `start'
/home/robert/.rvm/gems/ruby-1.9.3-p327/gems/delayed_job-3.0.5/lib/delayed/tasks.rb:9:in `block (2 levels) in <top (required)>'
Tasks: TOP => jobs:work
(See full trace by running task with --trace)

我不知道出了什么问题——更令人惊讶的是，我能找到其他人问这个问题....！

感谢您的帮助！

【问题讨论】：

长话短说——我升级到 postgres 9.1 并且错误消失了。

标签： ruby-on-rails-3.2 delayed-job postgresql-8.4

【解决方案1】：

我遇到了完全相同的问题。我通过将延迟作业活动记录的 Gemfile 锁定到版本 0.3.3 解决了这个问题：

gem 'delayed_job_active_record', '0.3.3'

不工作的 gem 是 0.4.1 版，于 2012 年 2 月 12 日发布。

【讨论】：

我可以确认这个解决方案。 Gem delayed_job_active_record 版本 4.0.0 和 0.4.4 显示错误行为，但 gem 版本 0.3.3 正常运行。我正在使用 PostgresSQL 8.3.7。
要使用0.3.3版本的“delayed_job_active_record”，它需要active_record版本 2.1。我使用的是Rails4。任何其他替代方案的想法请...
Rails 4（见下面的答案）：gem 'delayed_job_active_record', :git => 'git@github.com:panter/delayed_job_active_record.git'

【解决方案2】：

更新 postgres 也为我解决了这个问题——这似乎比锁定回旧版本更可取。并不是说这是我的答案，但是当 rmosolgo 回答了他自己的问题时，似乎这个问题可以正确地进入“已接受答案”状态。

【讨论】：

您升级到哪个版本的 Postgres 以使其正常工作？
9.2.4 可能。这就是我现在的状态，从那以后我不记得升级了。我也许还应该注意我在 Windows 上运行它。（企业情况……）

【解决方案3】：

这是延迟作业的已知问题，请参阅https://github.com/collectiveidea/delayed_job_active_record/issues/33

delayed_job_active_record 的一个分支在 postgres 8.4 上运行良好，并且与 rails 4.x 兼容

gem 'delayed_job_active_record', :git => 'git@github.com:panter/delayed_job_active_record.git'

它通过使用 postgres sql 调用解决了这个问题，而没有失败的查询。

【讨论】：

【解决方案4】：

我尝试使用 bt Neil Woods 提供的解决方案，但它显示了一些身份验证问题，然后我尝试在下面的行中添加一些相同的更改。

gem 'delayed_job_active_record', :git => 'git://github.com/panterch/delayed_job_active_record.git'

这个解决了，如果有人遇到同样的问题，请试试这个。

谢谢。

【讨论】：