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This term you store a table in your code.

This unit is Data Handling II: Databases & Structured Data.

A database is an organised set of tables. A database program keeps them and answers questions, fast. You will not use one this term. You will build its main steps: ask, keep the matches, count. A record is the facts about one thing, in one row. A field is one value in a row. A header is the name at the top of a column. A query is a question asked of a table. A tally is one count for each group.

What you will learn

• One record, one row — a row is four values kept together.
• The naming value — a key is a column. Each value names one record.
• Naming the columns — a header name becomes a position.
• Asking one condition — a query walks the rows, keeps the matches.
• Asking two conditions — a row must meet both.
• The answer, in order — the same sort, moving whole rows.
• Counting the groups — the tally counts the answer, not the table.
• What a database adds — it can give your answer on bigger tables.

Need a quick recap?

• Rows and columns — one row per record, one column per fact.
• One list, many values — a row is one list of values.
• Positions — a field sits at a position, counted from 0.