Confused and not clear docs about `serialize`
vitonsky opened this issue · comments
Robert Vitonsky commented
Issue Summary
I need to execute few SQL queries and wrap it in transaction, to ensure data consistency.
I see DB have method serialize
and i've read the docs https://github.com/tryghost/node-sqlite3/wiki/Control-Flow
It is absolutely not clear how this method works technically. Some questions i have after read:
- How works this wrapper? Why SQL queries inside callback will executes one by one?
- Can i wrap callbacks to promises? Is it will still executes one by one?
- How to wrap to promises to make my code with complex request inside transaction are flatten?
Steps to Reproduce
- Go to https://github.com/tryghost/node-sqlite3/wiki/Control-Flow
- Read the docs and try to understand how
serialize
works under the hood, and how to create flat async code with few SQL queries inside transaction
Version
5.1.6
Node.js Version
v18.16.0
How did you install the library?
npm i sqlite3
Jonathan Leonard commented
For promises, I created prun
using p/deferred from the promesa library in clojurescript:
(defn- prun [db sql & [args]]
(let [p (p/deferred)]
#_(js/console.debug (format "running sql: %s with args: %s" sql args))
(.run db sql (if args (clj->js args) #js [])
(fn [err]
(if err
(p/reject! p (js->clj err))
(p/resolve! p (this-as t {:last-id (.-lastID t)
:changes (.-changes t)})))))
p))
You could do similarly in plain JavaScript.