title: Oracle 12c Adding Column to table without default value taking really long
body: <p>I'm trying to add a new column to an existing table of approximately 30,000 rows in our test Oracle 12c R2 environment, but it has been running for over an hour and completely locked up SQL Developer</p>
  
  <p>Here is the basic syntax that I used. I didn't specify any default value since one isn't needed and should be NULL by default.</p>
  
  <pre><code>ALTER TABLE "Schema"."Table" ADD "C_C6" VARCHAR2(8 BYTE)
  </code></pre>
  
  <p>I tried looking up this issue, but most cases seem to refer to issues where people are trying to specify default values, which I'm not doing.</p>
  
  <p>I have also temporarily disable any triggers that I had on the table prior to running the Alter Table statement</p>
  
  <p>Any suggestions?</p>