title: MySQL Cannot add Foreign Key Constraint to tables
body: <p>I am having trouble adding Foreign Key constraints to my database.</p>
  
  <p>I am running the InnoDB engine on all tables, and have insured the data type and size are the same in both tables. </p>
  
  <p>Also, I have tried using the MySQL command line, phpMyAdmin and MySQL workbench, but no luck.</p>
  
  <p>Since in MySQL workbench does not allow me to check the Index Columns, nor select the Referenced Column, there is another issue I am overlooking.</p>
  
  <p>Is there something else I should be looking for?</p>
  
  <p>I do have test data in almost all of the tables, would that matter?</p>
  
  <p>EDIT: When I do see an error it is usually "#1005 - Can't create table 'db_name.#sql-43d_8e' (errno: 150)" , that talks about data mismatching, according to the documentation...Otherwise MySQL Workbench won't let me do it, so I do no know the problem.</p>