动态的预备陈述是否有意义？

Question

I want to create dynamic prepared statements, that every part is dynamic, the values, the table and the WHERE part.

I use nodejs + PostgreSQL and the pg module to talk to the PostgreSQL. The pg module offers a different syntax to go along with node.js , but I guess the principles are the same. This is based to the official example here

//dynamic that can change 
let select = 'name , email, age';
let table = 'user';
let where = 'id=$1 AND gender=$2';
let values = [1,'female'];

//prepare
const query = {
  // give the query a unique name  
  name: 'fetch-user',
  text: 'SELECT' + select + 'FROM' + table + 'WHERE' + where,
  values: values
}

//execute
client.query(query)
  .then(res => console.log(res.rows[0]))
  .catch(e => console.error(e.stack))

I was wondering if this will make sense , performance-wise .

I red the documentation and , what I understand is that by having all the parts of a prepared statement dynamic, then the planning may be not so effective , or not effective at all.

What should I do? Should I keep this dynamic syntax? Or it doesn't make any sense, so I have to create multiple prepared statements and use them for different tables?

Thanks

Answer 1

There should be no performance issues here. The "dynamic" part of your SQL is just a string you're passing into the query object, so the only performance to consider is resolving the text property. You're passing your database a fully prepared statement; it's nodejs that is resolving the different variables to come up with the query object's text property.