fetchFields
Executes the query and returns the first column of every row, mapped to T.
Declare T nullable when the column can be SQL NULL — fetchFields<String?>().
Return
The first column of all matching rows; empty when nothing matched.
Parameters
params
Values for $1, $2, … in declaration order.
Type Parameters
T
The type the column is mapped to.
Throws
REQUIRED_ATTRIBUTE_MISSING if a value is NULL and T is not nullable.