Issue Summary

Since #2174 was merged in 2017, the svv_columns system view has been updated to include late-binding views. This results in duplicate columns being returned by Redash's column aggregation query, which is creating front-end errors when I go to view a table's columns using the schema browser:

Error: "[ngRepeat:dupes] Duplicates in a repeater are not allowed. Use 'track by' expression to specify unique keys. Repeater: column in table.columns track by column, Duplicate key: teamid, Duplicate value: teamid
http://errors.angularjs.org/1.5.11/ngRepeat/dupes?p0=column%20in%20table.columns%20track%20by%20column&p1=teamid&p2=teamid"

Steps to Reproduce

1. Create a late-binding view in Redshift
2. Try to view its columns using the schema explorer in Redash
3. Note the JS errors in the browser console

Technical details:

• Redash Version: 5.0.0
• Browser/OS: Firefox (Quantum) 65.0.1/MacOS 10.14
• How did you install Redash: Setup script