Relations and formulas

Databases get powerful when they stop being islands. Relations connect records across databases; formulas compute new values out of the fields you already have.

Relations

A relation field links records in one database to records in another — tasks to a project, deals to a company, invoices to a client.

• Add a field with type Relation and pick the database it points to.
• On each record, the field holds one or more linked records, picked from a search.
• The link is two-way: the related database gets a mirror field showing the connection from its side.

Once related, a project’s page can show its tasks, and each task knows its project — the structure mirrors how the work actually connects.

Formulas

A formula field computes its value from other fields on the same record — it’s read-only and always up to date.

• Arithmetic and text: price * quantity, joining a first and last name
• Dates: days until a deadline, age of a record
• Conditions: label a task “Overdue” when the due date has passed
• Across relations: pull in or aggregate values from linked records — a project’s task count, the total of its invoices
• Across the whole database: totals, shares, and values from one specific record with column and lookup
• Lists and composition: transform, filter, find, or test related values with map, filter, find, some, and every
• People and records: read structured IDs, names, emails, and object properties
• Typed results: return numbers, text, checkboxes, dates, date ranges, lists, people, records, rich text, or JSON

The formula editor is designed to be explored rather than memorized. Type a property or function name for autocomplete, or insert one from the searchable library. Properties appear by their familiar labels, errors point to the exact part that needs attention, and a live preview shows the result before you save. Arithmetic supports the usual +, -, *, /, %, and ^ operators, while the function library covers conditions, text, dates, lists, aggregates, trigonometry, logarithms, regex text tools, people, records, and rich output.

Use current and index inside list functions:

map(related(projects, budget), round(current * 1.1, 2))

Use relatedRecords(projects) when you need linked record IDs or titles; related(projects, budget) remains the explicit, permission-scoped way to read a target property.

Reading other records in the same database

column(property) returns that property’s value on every record in the database, oldest first, so the usual list functions work on a whole column:

amount / sum(column(amount)) // this record's share of the total
count(filter(column(status), current == "Done"))

lookup reads one property from one other record. Give it a record’s name and the property to return, or, with three arguments, a property to match first:

lookup("Gold", price) // Price on the record named Gold
quantity * lookup(code, currency, rate)

Records in Trash are left out. A formula that uses column or lookup updates whenever any record in the database changes, so it can’t be read by another column or lookup, and the live preview shows its result only after you save. Very large databases (more than 2,000 records) refresh these formulas in the background within a few seconds. column and lookup read at most 10,000 records; in a larger database these formulas are empty. The result is copied to every record, so it can be up to 1,000 characters: use sum, count or join on a whole column rather than returning the list. Totals are worked out once for the whole database, but a formula that compares each record with a whole column, such as a rank, does work for every pair of records; it stays empty in databases of more than about 1,500 records.

Use let or lets when an intermediate value has a useful name:

lets(subtotal, price * quantity, tax, subtotal * 0.2, subtotal + tax)

Conditions can use either if(...), ifs(...), or the compact condition ? value : fallback form. Open Guide in the editor and search a function to see its syntax, description, example, and insert it directly.

Together

The pattern that carries most teams: one database per real-world thing (projects, tasks, people, clients), relations to express how they connect, and a few formulas for the numbers you keep re-computing by hand. Views over that — covered in Views and filters — do the rest.