For example:
const update = ({title, price, imageUrl, description, whereId, whereTitle }) => {
return db.query(
`UPDATE products
SET title=$1,
price=$2,
"imageUrl"=$3,
description=$4
WHERE
id=$5,
title ILIKE '%$6%'
`,
[title, price, imageUrl, description, whereId, whereTitle],
)
}
update({
whereId: 1,
title: 'Aliens 2: Electric Boogaloo',
description: 'Best sequel ever',
})
// shall execute this query:
// UPDATE products SET title='Aliens 2: Electric Boogaloo', description'Best sequel ever' WHERE id=1
// and keeping the price, "imageUrl" untouched / previous value
update({
whereTitle: 'godfather',
price: 20,
})
// shall execute this query:
// UPDATE products SET price=20 WHERE title ILIKE '%godfather%'
// or set the price of every products that contain the word 'godfather' as $20
// and keeping the title, "imageUrl", description, id untouched / previous value
Right now, I have to create a query for every possible query
SET title WHERE id
SET title, price WHERE id
SET price, "imageUrl" WHERE title
...
Which is not very dry, therefore I think there must be a better way of doing it
Edit 1:
This is what I imagine the code would look like.
db.query(
`UPDATE products
SET
title !== null? "title=$1," : skipToNextLine()
price !== null? "price=$2," : skipToNextLine()
"imageUrl" !== null? "\"imageUrl\"=$3," : skipToNextLine()
description !== null? "description=$4" : skipToNextLine()
whereId !== null && whereTitle !== null? "WHERE" : skipToNextLine()
whereId !== null? "id=$5," : skipToNextLine()
whereTitle !== null? "title ILIKE '%$6%'" : skipToNextLine()
`,
[title, price, imageUrl, description, whereId, whereTitle],
)
I do it in a style of ternary expression but there are plenty of other styles. I think the idea is similar to html's templating language like pug.js, ejs, handlebars, etc. There must be a way other than writing dozens of static html files for your html.
Edit 2:
I used string concatenation for quick and dirty solution, but I wonder if it is vulnerable to SQL injection. The code also becomes very long and code reliability / ease of comprehension drops significantly.
Here is my current solution:
const update = ({
title,
price,
imageUrl,
description,
whereId,
whereTitle,
}) => {
let queryText = 'UPDATE products SET'
let queryValue = []
let dollarCounter = 1
if (!!title) {
queryText = queryText.concat(` title=$${dollarCounter},`)
queryValue.push(title)
dollarCounter++
}
if (!!price) {
queryText = queryText.concat(` price=$${dollarCounter},`)
queryValue.push(price)
dollarCounter++
}
if (!!imageUrl) {
queryText = queryText.concat(` "imageUrl"=$${dollarCounter},`)
queryValue.push(imageUrl)
dollarCounter++
}
if (!!description) {
queryText = queryText.concat(` description=$${dollarCounter},`)
queryValue.push(description)
dollarCounter++
}
queryText = queryText.slice(0, -1)
if (!!whereId || !!whereTitle) queryText = queryText.concat(' WHERE')
if (!!whereId) {
queryText = queryText.concat(` id=$${dollarCounter},`)
queryValue.push(whereId)
dollarCounter++
}
if (!!whereTitle) {
queryText = queryText.concat(` title ILIKE '%$${dollarCounter}%',`)
queryValue.push(whereTitle)
dollarCounter++
}
queryText = queryText.slice(0, -1)
const query = {
name: 'update',
text: queryText,
values: queryValue,
}
return db.query(query)
}