API/Queries/Attributes.md

@@ -618,7 +618,7 @@ GROUP BY me.id, me.name, me.label, me.description, me.modifying_action, me.modif
 # Permitted Column Names
 
 Wherever a column is defined, it may be a simple name if it's unique e.g. `id`, or with the entity prefix `me.id`.
-For json(b) columns, a selector may be defined: `data->>'ident'` or `me.data->>'ident'.
+For json(b) columns, a selector may be defined: `data->>'ident'` or `me.data->>'ident'`.
 
 # Permitted functions
 
@@ -632,6 +632,10 @@ For any attribute which allows to call a function, this function must be permitt
 
 other permitted functions may be listed for a project.
 
+The function parameters may be anything conforming to the column names regex (so currently apart from column references integer and real numbers and 'null').
+
+The whole function call may not contain spaces. E.g. `coalesce(me.id,1)` must not be written as `coalesce(me.id, 1)`.
+
 # Naming Conventions
 
 When referencing to a column, the name without the table prefix can be used as long as it is unique within