Home / AI glossary / What does a data analyst do?

What does a data analyst do?

In short

A data analyst turns data a business already has into answers it can act on: building reports and dashboards, checking whether a number is real or an artefact, and explaining what changed and why. They work mostly in SQL, spreadsheets and a BI tool, and their output is a decision, not a pipeline.

A data analyst turns data a business already holds into answers it can act on. In practice that means building the reports and dashboards people actually read, checking whether a number is real or an artefact of how it was counted, and explaining what changed and why — usually in SQL, a spreadsheet and a BI tool.

The output of the job is a decision, not a dataset. An analyst who produces a beautiful dashboard nobody uses has not done the work; one who tells you that your margin fell because of one customer's return rate has.

What does a data analyst do day to day?

Four recurring activities. Pulling data out of the systems that hold it, usually with SQL. Cleaning it, which takes far longer than anyone budgets and is where most errors are caught. Analysing — comparing periods, segmenting, testing whether a difference is meaningful or noise. And communicating: a chart, a short written conclusion, a recommendation someone can act on this week. The last one is what separates a good analyst from a report generator.

Data analyst vs data engineer vs data scientist

An analyst answers questions with data that exists. A data engineer builds the plumbing that makes that data arrive reliably. A data scientist builds models that predict or classify rather than describe. In a company under fifty people these are usually the same person wearing three hats, and the honest sequence is analyst first — there is no point predicting next quarter if nobody trusts last quarter's number.

When does an SME need a data analyst?

When decisions are being delayed or argued about because nobody agrees on the number, and when the person currently producing reports is doing it as an evening job on top of another role. Below that threshold a well-built dashboard and a clear definition of each metric usually solves it. Above it, the cost of not having one shows up as decisions made on the loudest opinion in the room.

Do you need a data warehouse first?

Usually not to start. An analyst can work directly against your operational systems for a first set of questions, and doing so surfaces exactly which data problems are worth solving. A warehouse earns its cost when several systems must be combined routinely and the manual joining becomes the bottleneck — the threshold set out in do you need a data warehouse.

Frequently asked questions

What tools does a data analyst use?

Fewer than the job adverts imply. The core is stable and has been for years.

  • SQL for getting data out — the single most-used skill in the role.
  • A BI tool (Power BI, Looker Studio, Metabase) for reporting people can self-serve.
  • Spreadsheets for quick work, and Python or R when the analysis outgrows them.

Can AI replace a data analyst?

It replaces parts of the task and none of the responsibility. Models are now good at writing queries and drafting explanations.

  • What they cannot do is know that a spike in July was a system migration, not demand.
  • Context about your business is the analyst's actual asset, and it is not in the data.
  • The realistic outcome is one analyst covering more ground, not none.

Should we hire an analyst or outsource the work?

Depends on whether the questions are recurring or one-off.

  • Recurring reporting embedded in weekly decisions argues for hiring — the context compounds.
  • A one-off question, a migration, or building the first reporting layer is well suited to external help.
  • A common middle path is external setup, internal running.
Go deeper with Crux Digits

Want this applied in your business? See how we take it to production:

← All AI terms

From concept to working tool?

We build this AI in production — at fixed prices, with one named expert. Start with a free consultation.

Book a free consultation →