title: Update all rows of a single column
body: <p>I'm dealing with two tables which have 2 columns, as listed under.</p>
  
  <p>Table 1: table_snapshot
  account_no | balance_due</p>
  
  <p>Table 2: table_ paid
  account_no | post_balance | delta_balance</p>
  
  <p>I added a third column to table2 with the following command:</p>
  
  <pre><code>ALTER TABLE table_paid ADD delta_balance number(18);
  </code></pre>
  
  <p>I'm trying to use the following query, to update the new column ( delta_balance ) with the difference in balances between 1 and 2.
  FYI, table_paid is a subset of table_snapshot. i,e., table 2 has only a few accounts present in table 1. I get an error saying : SQL Statement not properly ended. the query i'm using is:</p>
  
  <pre><code>UPDATE table_paid
  SET table_paid.delta_balance = table_paid.post_balance - table_snapshot.balance_due
  from table_paid, table_snapshot
  WHERE table_paid.account_no = table_snapshot.account_no;
  </code></pre>
  
  <p>Appreciate if someone can correct my query.</p>
  
  <p>Many thanks.</p>
  
  <p>novice.</p>