---
kind: guide
zz: "0.9.0"
updated: 2026-10-14
state: live
rules: https://zriz.io/llms.txt
---
# Test that a database query is fast enough

Add a time budget to a SQL step of a zriz pipeline. The step fails when the query needs more milliseconds than your limit.

## The problem {#problem}

A query is slow when an index is missing or a table grows. The result stays correct, so a test of the rows does not see it. The page that uses the query gets slow.

## The test {#test}

The example is a shop API with a MySQL database. The query counts the rows of the table `users`. It must take under 50 ms.

Start from a project that `zz init` made: the [quick start](https://zriz.io/docs.md) gives the commands. Add the database value and the database resource.

`.zriz/environments/local.json`:

```json
{
  "values": {
    "TARGET_URL": "http://localhost:9080",
    "SHOP_DB": "user:pass@tcp(localhost:3306)/shop"
  },
  "sensitive": ["SHOP_DB"]
}
```

`.zriz/resources/shopdb.json`:

```json
{
  "type": "sql",
  "connection": "${env.SHOP_DB}",
  "read-only": true,
  "actions": {
    "count-users": { "query": "SELECT COUNT(*) AS total FROM users" }
  }
}
```

`.zriz/pipelines/query-is-fast.json`:

```json
{
  "description": "The user count takes under 50 ms",
  "steps": [
    {
      "call": "shopdb/count-users",
      "expect": [
        ["row-count", "==", 1],
        ["timing.target-ms", "<", 50]
      ]
    }
  ]
}
```

## Run it {#run}

```sh
zz run query-is-fast
```

```text
"status":"pass"
```

## What it proves {#proves}

- `timing.target-ms < 50`: the query and the read of the rows were fast enough. A slow query fails the step. The reason is `assertion`: `timing.target-ms is 212 and the pipeline expects 50`.
- `row-count == 1`: the query returned its result. A query that returns nothing fast does not pass.

- The runner measures the time next to your database, in your network.
- The number has no time for the connection and none for the prepare of the statement. A query with a syntax error has no number.

> Common mistake: A small test table is always fast. Use a database with data like production.

## Next {#next}

- [Test the response time of an API](https://zriz.io/learn/test-api-response-time.md)
- [Pipelines](https://zriz.io/docs/pipelines.md) gives each rule of the time budget, also for browser and command steps.