Step 7: Store links in a database

A Map disappears when the server restarts. Design two tables: links (id, target, creation time) and clicks (one row per visit, with the link id and a referrer). One row per click, instead of a counter column, is what lets you answer new questions later: clicks per day, where visitors came from. The index on link_id keeps those queries fast.

Examplesql

Open in editor »

Now the analytics questions the statistics page needs:

Examplesql

Open in editor »

Quick check

Why store one row per click instead of one counter?

You can answer new questions later, like clicks per dayCounters are not allowed in SQLIt uses less space

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

Tip: use the left and right arrow keys to move between lessons.