Using Trevor

Everything you need to know to become a data superstar with Trevor.io.

😎 Product updates

🧐 How do I...?

  • Give temporary access to our team

    If you need support with a query, or think you have found a bug, you can share temporary 24 hour access with our team in order to test or...

  • Add a link

    If you want to easily connect from your query in Trevor to a web link, or hyperlink, you can do this by adding a new column. You will nee...

  • Limit results

    If you want to limit the results from your query that are displayed, there are a couple of ways to do that. You can add a filter - maybe...

  • Connect to Sandbox

    If you don't have your own database, or you want to play around with some sample data before connecting, you can check out our Sandbox da...

  • Forecasting with Trevor

    If you're looking to get a predictive number or forecast from your existing data to say where you're going to end up at the end of the mo...

  • Expand JSON

    To expand JSON, click the header of the column you want to expand. Then, in the dropdown you should see a JSON section: Select this and ...

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🥷 SQL in Trevor.io

  • Writing raw SQL

    Yes you can! Simply: Head to the Query Builder tab.  Click Start New Query button.  Select the SQL option.  You can even write SQL, and...

  • SQL snippets in Trevor

    If you're used to writing SQL, it'll take you just a few minutes to get used to Trevor.io's interface.  In Trevor.io, you build queries ...

  • Count distinct values

    In Trevor.io, you can use the Summarize step to perform aggregate functions. To count distinct values, simply: Add a Summarize step Clic...

👉 Example queries

  • Trevor chart types

    Dashboard table A dashboard table chart will display the data in the same way as it's shown in your query. You can configure the max row...

🙊 Troubleshooting

  • Error : syntax error at or near "$1"

    If you come across this error message:   Error : syntax error at or near "$1"   This is due to the ' ? ' operator. You will need to swit...

  • 'Cycle detected' error message

    If you are joining queries together, you might come across this error message: This message is caused because the join has generated a '...

  • My table isn't available

    If you can't find a particular table in the 'Tables' dropdown list, it may be that it hasn't been configured as available. If you are an ...

  • Speed up slow queries

    Here are some things you can do to make your queries run faster: 1️⃣ Reduce the size of your data set by adding an early filter.  Try add...

  • Query suddenly slow

    If a query that usually runs very quickly suddenly takes much longer, then it's possible your database is dealing with some other load.  ...

  • Duplicate rows

    If you've notice the presence of duplicate rows, or multiple rows for one line item in your query, don't worry! Usually this is caused by...

🔗 Intro to joins

  • What is a join?

    Joining refers to combining rows from two or more database tables. Imagine a simple database with just 2 tables: A Customers table An...

  • Types of join

    In this post, the left table (or table A), means the table you're starting from. The right table (or table B), means the table you're ...

  • Database table relationships

    Three types of relationship exist between related tables.  1️⃣ One-to-One One record in a table is associated with one record, and only o...