The table columns grid

The Columns step of a Warehouse table popup shows every column of the table as an editable row. Dimension, Fact, Dictionary and Static tables use this grid, and the View wizard uses the same one. Read this page when a cell will not accept a change, when saving reports a message, or when you reorder columns or set a primary key; for the step-by-step editing flow, see Define table columns.

Note

Nothing in the grid is stored until the step is saved. The grid and the step's footer work on the same edited rows, and edits you have not saved survive closing and reopening the same table popup.

What the grid holds

Rows sit under six group headings:

Group	What it holds
Primary Key Columns	The unique identifier fields used as the primary key.
User Defined Columns	Your own business fields, fully editable and configurable.
Source Reference Columns	Fields that connect to a data source, used for data lineage and traceability.
Partition Columns	Partitioning fields, used to organise the table and speed up queries against it.
Audit Columns	Tracking fields that the platform maintains for you.
History Columns	Fields used for historical data querying.

What you can change, cell by cell

Most cells are editable while their row is unlocked. Several cells carry their own rules:

Data Domain: locked when the row is locked or when the column holds a foreign key, unless that foreign key is an Array.
Data Type: editable only when the row is unlocked, the column has no foreign key, and Data Domain is Custom.
PII Domain: editable while the row is unlocked; on the Source ID row it stays editable even when the row is locked.
PK: offered only on Static tables, and never on frozen, locked, foreign key or computed rows.
M: blocked by a foreign key, a computed script or a locked row.
FK: blocked by a computed script or a locked row.
Permission Group: stays editable on the Delete Flag row even when the row is locked.
PC: never editable from the grid.
A Primary Key cell that maps an existing row is editable only on rows you have just added; saved rows keep it locked.

Domains and their default values have their own reference: Column data domains, defaults and PII.

Why a cell is locked

Hover over a locked cell to see the reason in its tooltip:

"System columns cannot be edited."
"This column is locked."
"This row is locked and cannot be edited."
"Foreign key columns cannot be edited."
"This field cannot be edited."

A locked cell never accepts an edit from the grid.

What saving checks

When you save the step, the grid checks the columns and shows the first problem it finds:

Message	What it means
"Please add at least one custom column."	The table has no user-defined column of your own.
"At least one user-defined column must be marked as a Primary Key."	A Static table needs one of your columns marked PK.
"Column name cannot be empty (Row ID: N)"	A column has no name; N locates its row.
"System reserved names found: ..."	A column of yours reuses a system column name; the message lists it.
"Duplicate column names found: ..."	Two columns share a name; the message lists it.

The reserved-name and duplicate checks ignore capital letters, so a name is also refused when it repeats another name in a different case.

A column you define cannot reuse a system column name. The system names are: Insert DateTime, Update DateTime, Delete DateTime, Source Id, Source System Id, Delete Flag, Effective From Date, Effective To Date, Insert Process ID, Update Process IDs, Security Labels, Valid From, Valid To, Snapshot Day and Snapshot DateTime.

A dot in a column name is allowed, but risky: SQL reads it as table.column. When you enter a dotted name, the grid warns: "Dots are risky in column names - Consider renaming. SQL reads them as table.column." After you save such a column, the grid adds a note: "Keep in mind that dot was used for column name(s) which is tricky and usually better to avoid as SQL reads them as table.column."

Reorder columns

Drag a row to move it. Only saved, unlocked rows take part in ordering; a row you have added but not saved yet stays at the end of the list.
When you drop a row, the columns it passes take new places, and the grid renumbers them when the step is saved. The order you leave the grid in is the order that is stored.
System columns and locked rows keep their place; you cannot move them.

Primary keys

On a Static table, mark at least one of your own columns as PK; the save check waits for it.
On a deployed Static table, a saved user-defined primary key freezes the PK column: the flags can then no longer be changed.

Questions, answered

Which tables use this columns grid?

Warehouse Dimension, Fact, Dictionary and Static tables show it on the Columns step, and the View wizard uses the same grid.

Why can't I change a column's Data Type?

Data Type is editable only while the row is unlocked, the column has no foreign key, and Data Domain is Custom. For every other domain, pick the domain itself and the type follows it. See Column data domains, defaults and PII.

Why is the Primary Key checkbox disabled on my column?

The PK flag is offered only on Static tables. There it is unavailable on frozen, locked, foreign key and computed rows.

Why can't I edit the Primary Key cell of a row I saved earlier?

Those cells are editable only on rows you have just added. Once the row is saved, the cell stays locked.

Why is the Partition Column cell not editable?

The grid never lets you change it: the PC cell shows which column is the table's partition column, and you cannot switch it to another column here.

Why is a cell locked?

Hover the cell: its tooltip names the reason. Typical causes are a system column, a locked column or row, or a foreign key.

Why can't I drag the column I just added?

Only saved, unlocked rows take part in ordering. A row you have just added stays at the end of the list until the step is saved; save first, then place it.

What happens to the other columns when I drag one?

They take new places around the row you dropped. When you save, the grid renumbers the affected columns, so the order you see when you leave the grid is the order that is stored.

Do my unsaved column edits survive if I close the popup?

Yes. Edits you have not saved come back when you reopen the same table popup.

Why does "Duplicate column names found" appear?

Two columns share a name. Capital letters are ignored, so Amount and amount are treated as the same name; rename one of them.