SQLKit for Swift

SQLKit is a SQL client abstraction layer for Swift. It's designed to permit access to any SQL engine through the same uniform, convenient interface.

SQLKit 0.0.2 is a preliminary proof-of-concept release. It includes no tests, and the only included SQL client, PostgreSQL, builds within the SQL module. Important work still needs to be done, particularly on handling of values. But it does work, and it includes some very useful features.

Synopsis

import Foundation
import SQLKit

// Information we'll need later.
let (dbURL, userIDs): (URL, [Int]) = ...

// A SQLDatabase represents connection settings to talk to a database.
// (Currently just the client and URL.)
// 
// "PostgreSQL" here is a type conforming to SQLClient. You don't use 
// SQLClients directly, but you can implement one yourself.
// 
// SQL includes an AnySQLClient type which allows your code to 
// dynamically connect to any registered database type.
let db = SQLDatabase<PostgreSQL>(url: dbURL)

// A SQLConnection<PostgreSQL> is an individual connection to the database.
let connection = try db.makeConnection()

// A SQLStatement represents a whole or partial statement. Values interpolated 
// into a SQLStatement will be passed through placeholders or escaped, unless 
// they are themselves SQLStatements.
let whereClause: SQLStatement
if userIDs.isEmpty {
  whereClause = ""
}
else {
  whereClause = "WHERE " + userIDs.map { "id = \($0)" }.joined(" OR ")
}

// Perform the actual query.
let users = try db.query("SELECT * FROM users \(whereClause)")

// A SQLQuery<PostgreSQL> represents the results of an individual query. It 
// is used for two things.
// 
// 1. Get `SQLColumnKey`s representing the columns in the result set:
let idKey = try users.columnKey(forName: "id", as: Int.self)
let nameKey = try users.columnKey(forName: "name", as: String?.self)

// 2. Access the rows through its iterator:
for user in users.rowIterator {
  let id = try user.value(for: idKey)
  let name = try user.value(for: nameKey) ?? "[no name]"
  print("\(id)\t\(name)")
}

Contributions

Will be accepted by pull request, but if you're modifying the design, talk to me first. I'm just a little bit opinionated.

For now, the code of conduct is this: The first person who is such an asshat that I have to draft a real code of conduct is probably going to be banned. Don't be the asshat.

Copyright

(C) 2016 Groundbreaking Software. Distributed under the MIT License.

Version history

• SQLKit 0.0.2 (newly renamed) adds documentation to most public types and members, redesigns the way you access the rows in a SQLQuery, and nips and tucks the APIs in various ways. Although this is a point release, it includes breaking changes. 0.0 releases are like that.

• SQL 0.0.1 is a very preliminary proof-of-concept release. It includes no tests or documentation, and the only included SQL client, PostgreSQL, builds within the SQL module.