FetchableRecord

Creates a record from row.

For performance reasons, the row argument may be reused during the iteration of a fetch query. If you want to keep the row for later use, make sure to store a copy: self.row = row.copy().

When the FetchableRecord type also adopts the standard Decodable protocol, you can use this dictionary to customize the decoding process from database rows.

For example:

// A key that holds a decoder's name
let decoderName = CodingUserInfoKey(rawValue: "decoderName")!

// A FetchableRecord + Decodable record
struct Player: FetchableRecord, Decodable {
    // Customize the decoder name when decoding a database row
    static let databaseDecodingUserInfo: [CodingUserInfoKey: Any] = [decoderName: "Database"]

    init(from decoder: Decoder) throws {
        // Print the decoder name
        print(decoder.userInfo[decoderName])
        ...
    }
}

// prints "Database"
let player = try Player.fetchOne(db, ...)

// prints "JSON"
let decoder = JSONDecoder()
decoder.userInfo = [decoderName: "JSON"]
let player = try decoder.decode(Player.self, from: ...)

When the FetchableRecord type also adopts the standard Decodable protocol, this method controls the decoding process of nested properties from JSON database columns.

The default implementation returns a JSONDecoder with the following properties:

• dataDecodingStrategy: .base64
• dateDecodingStrategy: .millisecondsSince1970
• nonConformingFloatDecodingStrategy: .throw

You can override those defaults:

struct Achievement: Decodable {
    var name: String
    var date: Date
}

struct Player: Decodable, FetchableRecord {
    // stored in a JSON column
    var achievements: [Achievement]

    static func databaseJSONDecoder(for column: String) -> JSONDecoder {
        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = .iso8601
        return decoder
    }
}

When the FetchableRecord type also adopts the standard Decodable protocol, this property controls the decoding of date properties.

Default value is .deferredToDate

For example:

struct Player: FetchableRecord, Decodable {
    static let databaseDateDecodingStrategy: DatabaseDateDecodingStrategy = .timeIntervalSince1970

    var name: String
    var registrationDate: Date // decoded from epoch timestamp
}

A cursor over all records fetched from the database.

// SELECT * FROM player
let players = try Player.fetchCursor(db) // Cursor of Player
while let player = try players.next() {  // Player
    ...
}

Records are iterated in the natural ordering of the table.

If the database is modified during the cursor iteration, the remaining elements are undefined.

The cursor must be iterated in a protected dispath queue.

The selection defaults to all columns. This default can be changed for all requests by the TableRecord.databaseSelection property, or for individual requests with the TableRecord.select method.

An array of all records fetched from the database.

// SELECT * FROM player
let players = try Player.fetchAll(db) // [Player]

The selection defaults to all columns. This default can be changed for all requests by the TableRecord.databaseSelection property, or for individual requests with the TableRecord.select method.

The first found record.

// SELECT * FROM player
let player = try Player.fetchOne(db) // Player?

The selection defaults to all columns. This default can be changed for all requests by the TableRecord.databaseSelection property, or for individual requests with the TableRecord.select method.

Returns a cursor over records, given their primary keys.

let players = try Player.fetchCursor(db, keys: [1, 2, 3]) // Cursor of Player
while let player = try players.next() { // Player
    ...
}

Records are iterated in unspecified order.

Returns an array of records, given their primary keys.

let players = try Player.fetchAll(db, keys: [1, 2, 3]) // [Player]

The order of records in the returned array is undefined.

Returns a single record given its primary key.

let player = try Player.fetchOne(db, key: 123) // Player?

Returns a cursor over records identified by the provided unique keys (primary key or any key with a unique index on it).

// Cursor of Player
let players = try Player.fetchCursor(db, keys: [
    ["email": "a@example.com"],
    ["email": "b@example.com"]])
while let player = try players.next() { // Player
    ...
}

Records are iterated in unspecified order.

Returns an array of records identified by the provided unique keys (primary key or any key with a unique index on it).

// [Player]
let players = try Player.fetchAll(db, keys: [
    ["email": "a@example.com"],
    ["email": "b@example.com"]])

The order of records in the returned array is undefined.

Returns a single record identified by a unique key (the primary key or any key with a unique index on it).

let player = try Player.fetchOne(db, key: ["name": Arthur"]) // Player?

A cursor over records fetched from a prepared statement.

let statement = try db.makeSelectStatement(sql: "SELECT * FROM player")
let players = try Player.fetchCursor(statement) // Cursor of Player
while let player = try players.next() { // Player
    ...
}

If the database is modified during the cursor iteration, the remaining elements are undefined.

The cursor must be iterated in a protected dispath queue.

Returns an array of records fetched from a prepared statement.

let statement = try db.makeSelectStatement(sql: "SELECT * FROM player")
let players = try Player.fetchAll(statement) // [Player]

Returns a single record fetched from a prepared statement.

let statement = try db.makeSelectStatement(sql: "SELECT * FROM player")
let player = try Player.fetchOne(statement) // Player?

Returns a cursor over records fetched from an SQL query.

let players = try Player.fetchCursor(db, sql: "SELECT * FROM player") // Cursor of Player
while let player = try players.next() { // Player
    ...
}

If the database is modified during the cursor iteration, the remaining elements are undefined.

The cursor must be iterated in a protected dispath queue.

Returns an array of records fetched from an SQL query.

let players = try Player.fetchAll(db, sql: "SELECT * FROM player") // [Player]

Returns a single record fetched from an SQL query.

let player = try Player.fetchOne(db, sql: "SELECT * FROM player") // Player?

Returns a cursor over records fetched from a fetch request.

let request = try Player.all()
let players = try Player.fetchCursor(db, request) // Cursor of Player
while let player = try players.next() { // Player
    ...
}

If the database is modified during the cursor iteration, the remaining elements are undefined.

The cursor must be iterated in a protected dispath queue.

Returns an array of records fetched from a fetch request.

let request = try Player.all()
let players = try Player.fetchAll(db, request) // [Player]

Returns a single record fetched from a fetch request.

let request = try Player.filter(key: 1)
let player = try Player.fetchOne(db, request) // Player?