LayoutedColumnMapping

An array of (baseIndex, mappedName) pairs, where baseIndex is the index of a column in a base row, and mappedName the mapped name of that column.

Creates an LayoutedColumnMapping from an array of (baseIndex, mappedName) pairs. In each pair:

• baseIndex is the index of a column in a base row
• name is the mapped name of the column

For example, the following LayoutedColumnMapping defines two columns, foo and bar, based on the base columns at indexes 1 and 2:

LayoutedColumnMapping(layoutColumns: [(1, "foo"), (2, "bar")])

Use it in your custom RowAdapter type:

struct FooBarAdapter : RowAdapter {
    func layoutAdapter(layout: RowLayout) throws -> LayoutedRowAdapter {
        return LayoutedColumnMapping(layoutColumns: [(1, "foo"), (2, "bar")])
    }
}

// <Row foo:"foo" bar: "bar">
try Row.fetchOne(db, "SELECT NULL, 'foo', 'bar'", adapter: FooBarAdapter())

Part of the LayoutedRowAdapter protocol; returns self.

Part of the LayoutedRowAdapter protocol; returns the empty dictionary.

Part of the RowLayout protocol; returns the index of the leftmost column named name, in a case-insensitive way.