Use Examples on KvSQL.com

Use Example: A Cache With Expiry Using Key Reads and an SQL Sweep

Thu, 22 Oct 2026 00:00:00 +0000

A response cache has two jobs that pull in different directions. On a hit, it has to find one entry by its key as fast as possible. Now and then it has to throw away everything that has expired, which is a question over all the entries. In KvSQL both jobs run on one table.

db.execute("CREATE TABLE cache (key TEXT PRIMARY KEY, body BLOB, expires INTEGER NOT NULL);
            CREATE INDEX cache_expires ON cache(expires)", &[])?;

Store a response with put_row, which replaces an older entry under the same key:

Use Example: Settings Read by Key and Audited With SQL

Thu, 22 Oct 2026 00:00:00 +0000

Feature flags and settings are read all the time and listed rarely. The code asks “is the new checkout on?” on every request. Once in a while a person asks “what are all the search settings right now?” A plain keyspace in KvSQL answers both, with no schema at all.

Write settings as keys and values:

let mut tx = db.begin_write()?;
tx.put("settings", b"checkout.new_flow", b"on")?;
tx.put("settings", b"search.fuzzy", b"off")?;
tx.put("settings", b"search.limit", b"50")?;
tx.put("settings", b"upload.max_mb", b"20")?;
tx.commit()?;

Read one by key, straight from storage:

Use Example: Working With a Database File in the kvsql Shell

Thu, 22 Oct 2026 00:00:00 +0000

Sometimes you just want to look inside a database. Maybe a test left a file behind, or you’re checking what a service wrote, or you want to try a query before putting it in code. The kvsql shell opens a file directly, with no server running, and takes SQL and key-value commands side by side.

kvsql --file jobs.kvsql

Here is a short session, as the project’s use example program ran it through the shell’s own command code, one command at a time the way -c takes them. The output is exactly what came back: