Easy way to update data using node-postgres?

Question

I am using the excellent node-postgres plugin, https://github.com/brianc/node-postgres

I have this call for update. I have about 30 columns in my desk. Is there an easier way to update them this way?

/*
 Post /api/project/products/:pr_id HTTP/1.1
 */
exports.updateProduct = function(req, res){
  pg.connect(cs, function(err, client, done) {
    var query = "UPDATE products SET pr_title = ($1), pr_usercode = ($2) WHERE pr_id=($3)";
    client.query(query, [req.body.pr_title, req.body.pr_usercode, req.params.pr_id], function(err, result) {
      if (handleErr(err, done)) return;
      done();
      sendResponse(res, result.rows[0]);
    })
  });
};

I have only three columns. It will be dirty and hard to maintain when I write all 30 columns. There should be a way when just with a simple row to update all columns in req.body?

Any ideas?

Answer 1

You can always deploy a function like this:

function updateProductByID (id, cols) {
  // Setup static beginning of query
  var query = ['UPDATE products'];
  query.push('SET');

  // Create another array storing each set command
  // and assigning a number value for parameterized query
  var set = [];
  Object.keys(cols).forEach(function (key, i) {
    set.push(key + ' = ($' + (i + 1) + ')'); 
  });
  query.push(set.join(', '));

  // Add the WHERE statement to look up by id
  query.push('WHERE pr_id = ' + id );

  // Return a complete query string
  return query.join(' ');
}

And then use it as such:

/*
 Post /api/project/products/:pr_id HTTP/1.1
 */
exports.updateProduct = function(req, res){
  pg.connect(cs, function(err, client, done) {

    // Setup the query
    var query = updateProductByID(req.params.pr_id, req.body);

    // Turn req.body into an array of values
    var colValues = Object.keys(req.body).map(function (key) {
      return req.body[key];
    });

    client.query(query, colValues, function(err, result) {
      if (handleErr(err, done)) return;
      done();
      sendResponse(res, result.rows[0]);
    });
  });
};

, ORM - , , , , Knex.js

Answer 2

knexjs, postgre. javascript ( SQL-).

, , , . JSON ( ). , , .

function saveContactInfo( inputs, callback ) {
  var setObj = {};
  for( var property in inputs.contact )
  {
    //assumes properties are same as DB columns, otherwise need to use some string-mapping lookup.
    setObj[ property ] = inputs.contact[property];
  }
  setObj[ "LastModified" ] = new Date();

  var query = knex( "tblContact" ).update( setObj ).where( "contactId", inputs.contact.contactId );
  //log.debug("contactDao.saveContactInfo: " + query.toString());
  query.exec( function(err, results ){
    if(err) return callback(err);
    //Return from DB is usually an array, so return the object, not the array.
    callback( null, results[0] );
  });    
}

Knexjs postgre-only ( , MySQL)

Answer 3

exports.createInsertQuery = (tablename, obj) => {
    let insert = 'insert into ' + tablename;
    let keys = Object.keys(obj);
    let dollar = keys.map(function (item, idx) { return '$' + (idx + 1); });
    let values = Object.keys(obj).map(function (k) { return obj[k]; });
    return {
        query: insert + '(' + keys + ')' + ' values(' + dollar + ')',
        params: values
    }
}

let data = {firstname : 'hie' , lastname : 'jack', age : 4}
let yo = createInsertQuery('user',data) 

client.query(yo.query, yo.params ,(err,res) =>{
 console.log(res)
})

, , update,