No two rows with the same value

A product code, an employee number and an invoice number name one row. A page's record page and a printed code find a row by a field like this, and if two rows hold the same value, somebody opens the wrong one. Turn this on and Sterodata keeps each value to one row.

Turn it on

1. In Add Field, or in Edit field from the column's ⋮, open Rules and default.
2. Turn on No two rows can hold the same value.
3. Choose Save.

If the field already holds a value on more than one row, Sterodata does not turn it on and names the values, the most repeated first. Change or clear them, then turn it on.

These types take it: Text, Email, Phone, URL, Number and Date and time. It is not offered on a calculation, a lookup or a rollup, which keep nothing of their own; on a field of a Dynamic Table, which keeps no rows; on a column a connector fills, which takes what its source sends; or on a connected database, which keeps its own rules.

What counts as the same value

• Text is compared exactly. Capitals and accents count: A12 and a12 are two values, as are Ion and Ión.
• A number is compared as a number: 1.5 and 1.50 are one value.
• A date is compared as a date and time.
• Blank is not a value. Any number of rows can leave the field empty. A field with this on takes no default value, because every blank row would read as it.

When a value is taken

Sterodata refuses the write, saying which value and what to do: use a different value, or change the other row first. Nothing is changed. It holds however the row arrives, even if two people save the same value at the same moment:

• A cell in the grid, Add record and a batch of edits. A saved row keeps its own value without a clash.
• A paste, which stops at the row it cannot write and says so.
• A form, where the mark goes under the box the person typed in, in their language. This tells them the value is in use, so choose this for what a stranger may fairly learn, such as a booking code rather than an e-mail address.
• A button on a page's list, and an assistant writing over MCP, which reads the same sentence.
• An import, which is all or nothing: one repeated value, in the table or twice in the file, and no row of it is added.
• An automation writing rows, where the run stops and Runs says which value.

Deleted rows

A row in the trash holds nothing up: a new row can take its value. Undo on the deleted row is then refused, naming the value, until that other row changes.

Changing the field

A rename leaves the rule as it is, and so does a change between Text, Email, Phone and URL, which keeps the values as they are. A change that rewrites the values, such as text to number, could make two values one, so Sterodata asks you to turn the rule off first, change the type, then turn it on again. Deleting the field and restoring it from the trash brings the rule back with it.