title: How to upload .csv file into tables in Apex?
body: <p>I have question using Apex 5 for uploading data into tables through csv file format. Using the Data loading wizard, I was able to do it easily for all the columns but I want to know how to do it only for specific columns.</p>
  
  <p>For example, I have a table with three columns <code>x</code>, <code>y</code>, <code>z</code> and I have an Excel sheet with <code>y</code> and <code>z</code> data. <code>x</code> is a foreign key and its value has to be taken from another table. How can I insert only <code>y</code> and <code>z</code> data with <code>x</code> data coming from another table?</p>