Case
SQLTableConstraintAlgorithm.unique(columns:)
A
UNIQUE value constraint, also called a unique key, over one or more columns.case unique(columns: [any SQLExpression])
Discussion
In most SQL dialects, a UNIQUE constraint also implies the presence of an index over the constrained column(s), such that uniqueness is treated as a boolean attribute of such an index.
See also SQLColumnConstraintAlgorithm.unique.