IMPORTANT: This is the documentation for the latest SNAPSHOT
version. Please refer to the website at http://getquill.io for the lastest release's documentation.
Compile-time Language Integrated Query for Scala
Quill provides a Quoted Domain Specific Language (QDSL) to express queries in Scala and execute them in a target language. The library's core is designed to support multiple target languages, currently featuring specializations for Structured Query Language (SQL) and Cassandra Query Language (CQL).
- Boilerplate-free mapping: The database schema is mapped using simple case classes.
- Quoted DSL: Queries are defined inside a
quote
block. Quill parses each quoted block of code (quotation) at compile time and translates them to an internal Abstract Syntax Tree (AST) - Compile-time query generation: The
ctx.run
call reads the quotation's AST and translates it to the target language at compile time, emitting the query string as a compilation message. As the query string is known at compile time, the runtime overhead is very low and similar to using the database driver directly. - Compile-time query validation: If configured, the query is verified against the database at compile time and the compilation fails if it is not valid. The query validation does not alter the database state.
Note: The GIF example uses Eclipse, which shows compilation messages to the user.
The QDSL allows the user to write plain Scala code, leveraging scala's syntax and type system. Quotations are created using the quote
method and can contain any excerpt of code that uses supported operations. To create quotations, first create a context instance. Please see the context section for more details on the different context available.
For this documentation, a special type of context that acts as a mirror is used:
import io.getquill._
val ctx = new SqlMirrorContext(MirrorSqlDialect, Literal)
Note: Scastie is a great tool to try out Quill without having to prepare a local environment. It works with mirror contexts, see this snippet as an example.
The context instance provides all types and methods to deal quotations:
import ctx._
A quotation can be a simple value:
val pi = quote(3.14159)
And be used within another quotation:
case class Circle(radius: Float)
val areas = quote {
query[Circle].map(c => pi * c.radius * c.radius)
}
Quotations can also contain high-order functions and inline values:
val area = quote {
(c: Circle) => {
val r2 = c.radius * c.radius
pi * r2
}
}
val areas = quote {
query[Circle].map(c => area(c))
}
Quill's normalization engine applies reduction steps before translating the quotation to the target language. The correspondent normalized quotation for both versions of the areas
query is:
val areas = quote {
query[Circle].map(c => 3.14159 * c.radius * c.radius)
}
Scala doesn't have support for high-order functions with type parameters. It's possible to use method type parameter for this purpose:
def existsAny[T] = quote {
(xs: Query[T]) => (p: T => Boolean) =>
xs.filter(p(_)).nonEmpty
}
val q = quote {
query[Circle].filter { c1 =>
existsAny(query[Circle])(c2 => c2.radius > c1.radius)
}
}
Quotations are both compile-time and runtime values. Quill uses a type refinement to store the quotation's AST as an annotation available at compile-time and the q.ast
method exposes the AST as runtime value.
It is important to avoid giving explicit types to quotations when possible. For instance, this quotation can't be read at compile-time as the type refinement is lost:
// Avoid type widening (Quoted[Query[Circle]]), or else the quotation will be dynamic.
val q: Quoted[Query[Circle]] = quote {
query[Circle].filter(c => c.radius > 10)
}
ctx.run(q) // Dynamic query
Quill falls back to runtime normalization and query generation if the quotation's AST can't be read at compile-time. Please refer to dynamic queries for more information.
Quoting is implicit when writing a query in a run
statement.
ctx.run(query[Circle].map(_.radius))
// SELECT r.radius FROM Circle r
Quotations are designed to be self-contained, without references to runtime values outside their scope. There are two mechanisms to explicitly bind runtime values to a quotation execution.
A runtime value can be lifted to a quotation through the method lift
:
def biggerThan(i: Float) = quote {
query[Circle].filter(r => r.radius > lift(i))
}
ctx.run(biggerThan(10)) // SELECT r.radius FROM Circle r WHERE r.radius > ?
A Traversable
instance can be lifted as a Query
. There are two main usages for lifted queries:
def find(radiusList: List[Float]) = quote {
query[Circle].filter(r => liftQuery(radiusList).contains(r.radius))
}
ctx.run(find(List(1.1F, 1.2F)))
// SELECT r.radius FROM Circle r WHERE r.radius IN (?)
def insert(circles: List[Circle]) = quote {
liftQuery(circles).foreach(c => query[Circle].insert(c))
}
ctx.run(insert(List(Circle(1.1F), Circle(1.2F))))
// INSERT INTO Circle (radius) VALUES (?)
The database schema is represented by case classes. By default, quill uses the class and field names as the database identifiers:
case class Circle(radius: Float)
val q = quote {
query[Circle].filter(c => c.radius > 1)
}
ctx.run(q) // SELECT c.radius FROM Circle c WHERE c.radius > 1
Alternatively, the identifiers can be customized:
val circles = quote {
querySchema[Circle]("circle_table", _.radius -> "radius_column")
}
val q = quote {
circles.filter(c => c.radius > 1)
}
ctx.run(q)
// SELECT c.radius_column FROM circle_table c WHERE c.radius_column > 1
If multiple tables require custom identifiers, it is good practice to define a schema
object with all table queries to be reused across multiple queries:
case class Circle(radius: Int)
case class Rectangle(length: Int, width: Int)
object schema {
val circles = quote {
querySchema[Circle](
"circle_table",
_.radius -> "radius_column")
}
val rectangles = quote {
querySchema[Rectangle](
"rectangle_table",
_.length -> "length_column",
_.width -> "width_column")
}
}
It is possible to make a column that is a generated by the database to be ignored during insertions and returned as a returning value.
case class Product(id: Long, description: String, sku: Long)
val q = quote {
query[Product].insert(lift(Product(0L, "My Product", 1011L))).returning(_.id)
}
val returnedIds = ctx.run(q)
// INSERT INTO Product (description,sku) VALUES (?, ?)
Quill supports nested Embedded
case classes:
case class Contact(phone: String, address: String) extends Embedded
case class Person(id: Int, name: String, contact: Contact)
ctx.run(query[Person])
// SELECT x.id, x.name, x.phone, x.address FROM Person x
Note that default naming behavior uses the name of the nested case class properties. It's possible to override this default behavior using a custom schema
:
case class Contact(phone: String, address: String) extends Embedded
case class Person(id: Int, name: String, homeContact: Contact, workContact: Option[Contact])
val q = quote {
querySchema[Person](
"Person",
_.homeContact.phone -> "homePhone",
_.homeContact.address -> "homeAddress",
_.workContact.map(_.phone) -> "workPhone",
_.workContact.map(_.address) -> "workAddress"
)
}
ctx.run(q)
// SELECT x.id, x.name, x.homePhone, x.homeAddress, x.workPhone, x.workAddress FROM Person x
The overall abstraction of quill queries uses database tables as if they were in-memory collections. Scala for-comprehensions provide syntactic sugar to deal with these kind of monadic operations:
case class Person(id: Int, name: String, age: Int)
case class Contact(personId: Int, phone: String)
val q = quote {
for {
p <- query[Person] if(p.id == 999)
c <- query[Contact] if(c.personId == p.id)
} yield {
(p.name, c.phone)
}
}
ctx.run(q)
// SELECT p.name, c.phone FROM Person p, Contact c WHERE (p.id = 999) AND (c.personId = p.id)
Quill normalizes the quotation and translates the monadic joins to applicative joins, generating a database-friendly query that avoids nested queries.
Any of the following features can be used together with the others and/or within a for-comprehension:
val q = quote {
query[Person].filter(p => p.age > 18)
}
ctx.run(q)
// SELECT p.id, p.name, p.age FROM Person p WHERE p.age > 18
val q = quote {
query[Person].map(p => p.name)
}
ctx.run(q)
// SELECT p.name FROM Person p
val q = quote {
query[Person].filter(p => p.age > 18).flatMap(p => query[Contact].filter(c => c.personId == p.id))
}
ctx.run(q)
// SELECT c.personId, c.phone FROM Person p, Contact c WHERE (p.age > 18) AND (c.personId = p.id)
// similar to `flatMap` but for transformations that return a traversable instead of `Query`
val q = quote {
query[Person].concatMap(p => p.name.split(" "))
}
ctx.run(q)
// SELECT UNNEST(SPLIT(p.name, " ")) FROM Person p
val q1 = quote {
query[Person].sortBy(p => p.age)
}
ctx.run(q1)
// SELECT p.id, p.name, p.age FROM Person p ORDER BY p.age ASC NULLS FIRST
val q2 = quote {
query[Person].sortBy(p => p.age)(Ord.descNullsLast)
}
ctx.run(q2)
// SELECT p.id, p.name, p.age FROM Person p ORDER BY p.age DESC NULLS LAST
val q3 = quote {
query[Person].sortBy(p => (p.name, p.age))(Ord(Ord.asc, Ord.desc))
}
ctx.run(q3)
// SELECT p.id, p.name, p.age FROM Person p ORDER BY p.name ASC, p.age DESC
val q = quote {
query[Person].drop(2).take(1)
}
ctx.run(q)
// SELECT x.id, x.name, x.age FROM Person x LIMIT 1 OFFSET 2
val q = quote {
query[Person].groupBy(p => p.age).map {
case (age, people) =>
(age, people.size)
}
}
ctx.run(q)
// SELECT p.age, COUNT(*) FROM Person p GROUP BY p.age
val q = quote {
query[Person].filter(p => p.age > 18).union(query[Person].filter(p => p.age > 60))
}
ctx.run(q)
// SELECT x.id, x.name, x.age FROM (SELECT id, name, age FROM Person p WHERE p.age > 18
// UNION SELECT id, name, age FROM Person p1 WHERE p1.age > 60) x
val q = quote {
query[Person].filter(p => p.age > 18).unionAll(query[Person].filter(p => p.age > 60))
}
ctx.run(q)
// SELECT x.id, x.name, x.age FROM (SELECT id, name, age FROM Person p WHERE p.age > 18
// UNION ALL SELECT id, name, age FROM Person p1 WHERE p1.age > 60) x
val q2 = quote {
query[Person].filter(p => p.age > 18) ++ query[Person].filter(p => p.age > 60)
}
ctx.run(q2)
// SELECT x.id, x.name, x.age FROM (SELECT id, name, age FROM Person p WHERE p.age > 18
// UNION ALL SELECT id, name, age FROM Person p1 WHERE p1.age > 60) x
val r = quote {
query[Person].map(p => p.age)
}
ctx.run(r.min) // SELECT MIN(p.age) FROM Person p
ctx.run(r.max) // SELECT MAX(p.age) FROM Person p
ctx.run(r.avg) // SELECT AVG(p.age) FROM Person p
ctx.run(r.sum) // SELECT SUM(p.age) FROM Person p
ctx.run(r.size) // SELECT COUNT(p.age) FROM Person p
val q = quote {
query[Person].filter{ p1 =>
query[Person].filter(p2 => p2.id != p1.id && p2.age == p1.age).isEmpty
}
}
ctx.run(q)
// SELECT p1.id, p1.name, p1.age FROM Person p1 WHERE
// NOT EXISTS (SELECT * FROM Person p2 WHERE (p2.id <> p1.id) AND (p2.age = p1.age))
val q2 = quote {
query[Person].filter{ p1 =>
query[Person].filter(p2 => p2.id != p1.id && p2.age == p1.age).nonEmpty
}
}
ctx.run(q2)
// SELECT p1.id, p1.name, p1.age FROM Person p1 WHERE
// EXISTS (SELECT * FROM Person p2 WHERE (p2.id <> p1.id) AND (p2.age = p1.age))
val q = quote {
query[Person].filter(p => liftQuery(Set(1, 2)).contains(p.id))
}
ctx.run(q)
// SELECT p.id, p.name, p.age FROM Person p WHERE p.id IN (?, ?)
val q1 = quote { (ids: Query[Int]) =>
query[Person].filter(p => ids.contains(p.id))
}
ctx.run(q1(liftQuery(List(1, 2))))
// SELECT p.id, p.name, p.age FROM Person p WHERE p.id IN (?, ?)
val peopleWithContacts = quote {
query[Person].filter(p => query[Contact].filter(c => c.personId == p.id).nonEmpty)
}
val q2 = quote {
query[Person].filter(p => peopleWithContacts.contains(p.id))
}
ctx.run(q2)
// SELECT p.id, p.name, p.age FROM Person p WHERE p.id IN (SELECT p1.* FROM Person p1 WHERE EXISTS (SELECT c.* FROM Contact c WHERE c.personId = p1.id))
val q = quote {
query[Person].map(p => p.age).distinct
}
ctx.run(q)
// SELECT DISTINCT p.age FROM Person p
val q = quote {
query[Person].filter(p => p.name == "John").nested.map(p => p.age)
}
ctx.run(q)
// SELECT p.age FROM (SELECT p.age FROM Person p WHERE p.name = 'John') p
In addition to applicative joins Quill also supports explicit joins (both inner and left/right/full outer joins).
val q = quote {
query[Person].join(query[Contact]).on((p, c) => c.personId == p.id)
}
ctx.run(q)
// SELECT p.id, p.name, p.age, c.personId, c.phone
// FROM Person p INNER JOIN Contact c ON c.personId = p.id
val q = quote {
query[Person].leftJoin(query[Contact]).on((p, c) => c.personId == p.id)
}
ctx.run(q)
// SELECT p.id, p.name, p.age, c.personId, c.phone
// FROM Person p LEFT JOIN Contact c ON c.personId = p.id
The example joins above cover the simple case. What do you do when a query requires joining more than 2 tables?
With Quill the following multi-join queries are equivalent, choose according to preference:
case class Employer(id: Int, personId: Int, name: String)
val qFlat = quote {
for{
(p,e) <- query[Person].join(query[Employer]).on(_.id == _.personId)
c <- query[Contact].leftJoin(_.personId == p.id)
} yield(p, e, c)
}
val qNested = quote {
for{
((p,e),c) <-
query[Person].join(query[Employer]).on(_.id == _.personId)
.leftJoin(query[Contact]).on(
_._1.id == _.personId
)
} yield(p, e, c)
}
ctx.run(qFlat)
ctx.run(qNested)
// SELECT p.id, p.name, p.age, e.id, e.personId, e.name, c.id, c.phone
// FROM Person p INNER JOIN Employer e ON p.id = e.personId LEFT JOIN Contact c ON c.personId = p.id
Case Classes can also be used inside quotations as output values:
case class Person(id: Int, name: String, age: Int)
case class Contact(personId: Int, phone: String)
case class ReachablePerson(name:String, phone: String)
val q = quote {
for {
p <- query[Person] if(p.id == 999)
c <- query[Contact] if(c.personId == p.id)
} yield {
ReachablePerson(p.name, c.phone)
}
}
ctx.run(q)
// SELECT p.name, c.phone FROM Person p, Contact c WHERE (p.id = 999) AND (c.personId = p.id)
As well as in general:
case class IdFilter(id:Int)
val q = quote {
val idFilter = new IdFilter(999)
for {
p <- query[Person] if(p.id == idFilter.id)
c <- query[Contact] if(c.personId == p.id)
} yield {
ReachablePerson(p.name, c.phone)
}
}
ctx.run(q)
// SELECT p.name, c.phone FROM Person p, Contact c WHERE (p.id = 999) AND (c.personId = p.id)
Note however that this functionality has the following restrictions:
- The Ad-Hoc Case Class can only have one constructor with one set of parameters.
- The Ad-Hoc Case Class must be constructed inside the quotation using one of the following methods:
- Using the
new
keyword:new Person("Joe", "Bloggs")
- Using a companion object's apply method:
Person("Joe", "Bloggs")
- Using a companion object's apply method explicitly:
Person.apply("Joe", "Bloggs")
- Using the
- Any custom logic in a constructor/apply-method of a Ad-Hoc case class will not be invoked when it is 'constructed' inside a quotation. To construct an Ad-Hoc case class with custom logic inside a quotation, you can use a quoted method.
Query probing validates queries against the database at compile time, failing the compilation if it is not valid. The query validation does not alter the database state.
This feature is disabled by default. To enable it, mix the QueryProbing
trait to the database configuration:
object myContext extends YourContextType with QueryProbing
The context must be created in a separate compilation unit in order to be loaded at compile time. Please use this guide that explains how to create a separate compilation unit for macros, that also serves to the purpose of defining a query-probing-capable context. context
could be used instead of macros
as the name of the separate compilation unit.
The configurations correspondent to the config key must be available at compile time. You can achieve it by adding this line to your project settings:
unmanagedClasspath in Compile += baseDirectory.value / "src" / "main" / "resources"
If your project doesn't have a standard layout, e.g. a play project, you should configure the path to point to the folder that contains your config file.
Database actions are defined using quotations as well. These actions don't have a collection-like API but rather a custom DSL to express inserts, deletes and updates.
val a = quote(query[Contact].insert(lift(Contact(999, "+1510488988"))))
ctx.run(a)
// INSERT INTO Contact (personId,phone) VALUES (?, ?)
val a = quote {
query[Contact].insert(_.personId -> lift(999), _.phone -> lift("+1510488988"))
}
ctx.run(a)
// INSERT INTO Contact (personId,phone) VALUES (?, ?)
val a = quote {
liftQuery(List(Person(0, "John", 31))).foreach(e => query[Person].insert(e))
}
ctx.run(a)
// INSERT INTO Person (id,name,age) VALUES (?, ?, ?)
val a = quote {
query[Person].filter(_.id == 999).update(lift(Person(999, "John", 22)))
}
ctx.run(a)
// UPDATE Person SET id = ?, name = ?, age = ? WHERE id = 999
val a = quote {
query[Person].filter(p => p.id == lift(999)).update(_.age -> lift(18))
}
ctx.run(a)
// UPDATE Person SET age = ? WHERE id = ?
val a = quote {
query[Person].filter(p => p.id == lift(999)).update(p => p.age -> (p.age + 1))
}
ctx.run(a)
// UPDATE Person SET age = (age + 1) WHERE id = ?
val a = quote {
liftQuery(List(Person(1, "name", 31))).foreach { person =>
query[Person].filter(_.id == person.id).update(_.name -> person.name, _.age -> person.age)
}
}
ctx.run(a)
// UPDATE Person SET name = ?, age = ? WHERE id = ?
val a = quote {
query[Person].filter(p => p.name == "").delete
}
ctx.run(a)
// DELETE FROM Person WHERE name = ''
Upsert is only supported by Postgres and MySQL
Ignore conflict
val a = quote {
query[Product].insert(_.id -> 1, _.sku -> 10).onConflictIgnore
}
// INSERT INTO Product AS t (id,sku) VALUES (1, 10) ON CONFLICT DO NOTHING
Ignore conflict by explicitly setting conflict target
val a = quote {
query[Product].insert(_.id -> 1, _.sku -> 10).onConflictIgnore(_.id)
}
// INSERT INTO Product AS t (id,sku) VALUES (1, 10) ON CONFLICT (id) DO NOTHING
Resolve conflict by updating existing row if needed. In onConflictUpdate(target)((t, e) => assignment)
: target
refers to
conflict target, t
- to existing row and e
- to excluded, e.g. row proposed for insert.
val a = quote {
query[Product]
.insert(_.id -> 1, _.sku -> 10)
.onConflictUpdate(_.id)((t, e) => t.sku -> (t.sku + e.sku))
}
// INSERT INTO Product AS t (id,sku) VALUES (1, 10) ON CONFLICT (id) DO UPDATE SET sku = (t.sku + EXCLUDED.sku)
Ignore any conflict, e.g. insert ignore
val a = quote {
query[Product].insert(_.id -> 1, _.sku -> 10).onConflictIgnore
}
// INSERT IGNORE INTO Product (id,sku) VALUES (1, 10)
Ignore duplicate key conflict by explicitly setting it
val a = quote {
query[Product].insert(_.id -> 1, _.sku -> 10).onConflictIgnore(_.id)
}
// INSERT INTO Product (id,sku) VALUES (1, 10) ON DUPLICATE KEY UPDATE id=id
Resolve duplicate key by updating existing row if needed. In onConflictUpdate((t, e) => assignment)
: t
refers to
existing row and e
- to values, e.g. values proposed for insert.
val a = quote {
query[Product]
.insert(_.id -> 1, _.sku -> 10)
.onConflictUpdate((t, e) => t.sku -> (t.sku + e.sku))
}
// INSERT INTO Product (id,sku) VALUES (1, 10) ON DUPLICATE KEY UPDATE sku = (sku + VALUES(sku))
Quill provides an IO monad that allows the user to express multiple computations and execute them separately. This mechanism is also known as a free monad, which provides a way of expressing computations as referentially-transparent values and isolates the unsafe IO operations into a single operation. For instance:
// this code using Future
val p = Person(0, "John", 22)
ctx.run(query[Person].insert(lift(p))).flatMap { _ =>
ctx.run(query[Person])
}
// isn't referentially transparent because if you refactor the second database
// interaction into a value, the result will be different:
val allPeople = ctx.run(query[Person])
ctx.run(query[Person].insert(lift(p))).flatMap { _ =>
allPeople
}
// this happens because `ctx.run` executes the side-effect (database IO) immediately
// The IO monad doesn't perform IO immediately, so both computations:
val p = Person(0, "John", 22)
val a =
ctx.runIO(query[Person].insert(lift(p))).flatMap { _ =>
ctx.runIO(query[Person])
}
val allPeople = ctx.runIO(query[Person])
val b =
ctx.runIO(query[Person].insert(lift(p))).flatMap { _ =>
allPeople
}
// produce the same result when executed
performIO(a) == performIO(b)
The IO monad has an interface similar to Future
; please refer to the class for more information regarding the available operations.
The return type of performIO
varies according to the context. For instance, async contexts return Future
s while JDBC returns values synchronously.
NOTE: Avoid using the variable name io
since it conflicts with Quill's package io.getquill
, otherwise you will get following error.
recursive value io needs type
IO
also provides the transactional
method that delimits a transaction:
val a =
ctx.runIO(query[Person].insert(lift(p))).flatMap { _ =>
ctx.runIO(query[Person])
}
performIO(a.transactional) // note: transactional can be used outside of `performIO`
The IO monad tracks the effects that a computation performs in its second type parameter:
val a: IO[ctx.RunQueryResult[Person], Effect.Write with Effect.Read] =
ctx.runIO(query[Person].insert(lift(p))).flatMap { _ =>
ctx.runIO(query[Person])
}
This mechanism is useful to limit the kind of operations that can be performed. See this blog post as an example.
Quill provides implicit conversions from case class companion objects to query[T]
through an additional trait:
val ctx = new SqlMirrorContext(MirrorSqlDialect, Literal) with ImplicitQuery
import ctx._
val q = quote {
for {
p <- Person if(p.id == 999)
c <- Contact if(c.personId == p.id)
} yield {
(p.name, c.phone)
}
}
ctx.run(q)
// SELECT p.name, c.phone FROM Person p, Contact c WHERE (p.id = 999) AND (c.personId = p.id)
Note the usage of Person
and Contact
instead of query[Person]
and query[Contact]
.
Some operations are sql-specific and not provided with the generic quotation mechanism. The sql contexts provide implicit classes for this kind of operation:
val ctx = new SqlMirrorContext(MirrorSqlDialect, Literal)
import ctx._
val q = quote {
query[Person].filter(p => p.name like "%John%")
}
ctx.run(q)
// SELECT p.id, p.name, p.age FROM Person p WHERE p.name like '%John%'
Quill provides SQL Arrays support. In Scala we represent them as any collection that implements Seq
:
import java.util.Date
case class Book(id: Int, notes: List[String], pages: Vector[Int], history: Seq[Date])
ctx.run(query[Book])
// SELECT x.id, x.notes, x.pages, x.history FROM Book x
Note that not all drivers/databases provides such feature hence only PostgresJdbcContext
and
PostgresAsyncContext
support SQL Arrays.
val ctx = new CassandraMirrorContext(Literal)
import ctx._
The cassandra context provides List, Set and Map encoding:
case class Book(id: Int, notes: Set[String], pages: List[Int], history: Map[Int, Boolean])
ctx.run(query[Book])
// SELECT id, notes, pages, history FROM Book
The cassandra context provides encoding of UDT (user-defined types).
import io.getquill.context.cassandra.Udt
case class Name(firstName: String, lastName: String) extends Udt
To encode UDT and bind it into the query (insert/update queries), context needs to retrieve UDT metadata from
cluster object. By default, context looks for UDT within currently logged keyspace, but it's also possible to specify
concrete keyspace with udtMeta
:
implicit val nameMeta = udtMeta[Name]("keyspace2.my_name")
When keyspace is not set in udtMeta
then the currently logged is used.
Since it's possible to create context without specifying keyspace, e.g. keyspace parameter is null and session is not bound to any keyspace, UDT metadata is being resolved among all cluster.
It's also possible to rename UDT columns with udtMeta
:
implicit val nameMeta = udtMeta[Name]("name", _.firstName -> "first", _.lastName -> "last")
The cassandra context also provides a few additional operations:
val q = quote {
query[Person].filter(p => p.age > 10).allowFiltering
}
ctx.run(q)
// SELECT id, name, age FROM Person WHERE age > 10 ALLOW FILTERING
val q = quote {
query[Person].insert(_.age -> 10, _.name -> "John").ifNotExists
}
ctx.run(q)
// INSERT INTO Person (age,name) VALUES (10, 'John') IF NOT EXISTS
val q = quote {
query[Person].filter(p => p.name == "John").delete.ifExists
}
ctx.run(q)
// DELETE FROM Person WHERE name = 'John' IF EXISTS
val q1 = quote {
query[Person].insert(_.age -> 10, _.name -> "John").usingTimestamp(99)
}
ctx.run(q1)
// INSERT INTO Person (age,name) VALUES (10, 'John') USING TIMESTAMP 99
val q2 = quote {
query[Person].usingTimestamp(99).update(_.age -> 10)
}
ctx.run(q2)
// UPDATE Person USING TIMESTAMP 99 SET age = 10
val q1 = quote {
query[Person].insert(_.age -> 10, _.name -> "John").usingTtl(11)
}
ctx.run(q1)
// INSERT INTO Person (age,name) VALUES (10, 'John') USING TTL 11
val q2 = quote {
query[Person].usingTtl(11).update(_.age -> 10)
}
ctx.run(q2)
// UPDATE Person USING TTL 11 SET age = 10
val q3 = quote {
query[Person].usingTtl(11).filter(_.name == "John").delete
}
ctx.run(q3)
// DELETE FROM Person USING TTL 11 WHERE name = 'John'
val q1 = quote {
query[Person].insert(_.age -> 10, _.name -> "John").using(ts = 99, ttl = 11)
}
ctx.run(q1)
// INSERT INTO Person (age,name) VALUES (10, 'John') USING TIMESTAMP 99 AND TTL 11
val q2 = quote {
query[Person].using(ts = 99, ttl = 11).update(_.age -> 10)
}
ctx.run(q2)
// UPDATE Person USING TIMESTAMP 99 AND TTL 11 SET age = 10
val q3 = quote {
query[Person].using(ts = 99, ttl = 11).filter(_.name == "John").delete
}
ctx.run(q3)
// DELETE FROM Person USING TIMESTAMP 99 AND TTL 11 WHERE name = 'John'
val q1 = quote {
query[Person].update(_.age -> 10).ifCond(_.name == "John")
}
ctx.run(q1)
// UPDATE Person SET age = 10 IF name = 'John'
val q2 = quote {
query[Person].filter(_.name == "John").delete.ifCond(_.age == 10)
}
ctx.run(q2)
// DELETE FROM Person WHERE name = 'John' IF age = 10
val q = quote {
query[Person].map(p => p.age).delete
}
ctx.run(q)
// DELETE p.age FROM Person
requires allowFiltering
val q = quote {
query[Book].filter(p => p.pages.contains(25)).allowFiltering
}
ctx.run(q)
// SELECT id, notes, pages, history FROM Book WHERE pages CONTAINS 25 ALLOW FILTERING
requires allowFiltering
val q = quote {
query[Book].filter(p => p.history.contains(12)).allowFiltering
}
ctx.run(q)
// SELECT id, notes, pages, history FROM book WHERE history CONTAINS 12 ALLOW FILTERING
requires allowFiltering
val q = quote {
query[Book].filter(p => p.history.containsValue(true)).allowFiltering
}
ctx.run(q)
// SELECT id, notes, pages, history FROM book WHERE history CONTAINS true ALLOW FILTERING
Quill's default operation mode is compile-time, but there are queries that have their structure defined only at runtime. Quill automatically falls back to runtime normalization and query generation if the query's structure is not static. Example:
val ctx = new SqlMirrorContext(MirrorSqlDialect, Literal)
import ctx._
sealed trait QueryType
case object Minor extends QueryType
case object Senior extends QueryType
def people(t: QueryType): Quoted[Query[Person]] =
t match {
case Minor => quote {
query[Person].filter(p => p.age < 18)
}
case Senior => quote {
query[Person].filter(p => p.age > 65)
}
}
ctx.run(people(Minor))
// SELECT p.id, p.name, p.age FROM Person p WHERE p.age < 18
ctx.run(people(Senior))
// SELECT p.id, p.name, p.age FROM Person p WHERE p.age > 65
Infix is a very flexible mechanism to use non-supported features without having to use plain queries in the target language. It allows insertion of arbitrary strings within quotations.
For instance, quill doesn't support the FOR UPDATE
SQL feature. It can still be used through infix and implicit classes:
implicit class ForUpdate[T](q: Query[T]) {
def forUpdate = quote(infix"$q FOR UPDATE".as[Query[T]])
}
val a = quote {
query[Person].filter(p => p.age < 18).forUpdate
}
ctx.run(a)
// SELECT p.name, p.age FROM person p WHERE p.age < 18 FOR UPDATE
The forUpdate
quotation can be reused for multiple queries.
You can also use infix to port raw SQL queries to Quill and map it to regular scala tuples.
val rawQuery = quote {
(id: Int) => infix"""SELECT id, name FROM my_entity WHERE id = $id""".as[Query[(Int, String)]]
}
ctx.run(rawQuery(1))
//SELECT x._1, x._2 FROM (SELECT id AS "_1", name AS "_2" FROM my_entity WHERE id = 1) x
Note that in this case the result query is nested.
It's required since quill is not aware of a query tree and cannot safely unnest it.
This is different to the example above because infix starts with the query infix"$q...
where its tree is already compiled
A custom database function can also be used through infix:
val myFunction = quote {
(i: Int) => infix"MY_FUNCTION($i)".as[Int]
}
val q = quote {
query[Person].map(p => myFunction(p.age))
}
ctx.run(q)
// SELECT MY_FUNCTION(p.age) FROM Person p
You can implement comparison operators by defining implicit conversion and using infix.
import java.util.Date
implicit class DateQuotes(left: Date) {
def >(right: Date) = quote(infix"$left > $right".as[Boolean])
def <(right: Date) = quote(infix"$left < $right".as[Boolean])
}
implicit class OnDuplicateKeyIgnore[T](q: Insert[T]) {
def ignoreDuplicate = quote(infix"$q ON DUPLICATE KEY UPDATE id=id".as[Insert[T]])
}
ctx.run(
liftQuery(List(
Person(1, "Test1", 30),
Person(2, "Test2", 31)
)).foreach(row => query[Person].insert(row).ignoreDuplicate)
)
Quill uses Encoder
s to encode query inputs and Decoder
s to read values returned by queries. The library provides a few built-in encodings and two mechanisms to define custom encodings: mapped encoding and raw encoding.
If the correspondent database type is already supported, use MappedEncoding
. In this example, String
is already supported by Quill and the UUID
encoding from/to String
is defined through mapped encoding:
import ctx._
import java.util.UUID
implicit val encodeUUID = MappedEncoding[UUID, String](_.toString)
implicit val decodeUUID = MappedEncoding[String, UUID](UUID.fromString(_))
A mapped encoding also can be defined without a context instance by importing io.getquill.MappedEncoding
:
import io.getquill.MappedEncoding
import java.util.UUID
implicit val encodeUUID = MappedEncoding[UUID, String](_.toString)
implicit val decodeUUID = MappedEncoding[String, UUID](UUID.fromString(_))
Note that can it be also used to provide mapping for element types of collection (SQL Arrays or Cassandra Collections).
If the database type is not supported by Quill, it is possible to provide "raw" encoders and decoders:
trait UUIDEncodingExample {
val jdbcContext: PostgresJdbcContext[Literal] // your context should go here
import jdbcContext._
implicit val uuidDecoder: Decoder[UUID] =
decoder((index, row) =>
UUID.fromString(row.getObject(index).toString)) // database-specific implementation
implicit val uuidEncoder: Encoder[UUID] =
encoder(java.sql.Types.OTHER, (index, value, row) =>
row.setObject(index, value, java.sql.Types.OTHER)) // database-specific implementation
// Only for postgres
implicit def arrayUUIDEncoder[Col <: Seq[UUID]]: Encoder[Col] = arrayRawEncoder[UUID, Col]("uuid")
implicit def arrayUUIDDecoder[Col <: Seq[UUID]](implicit bf: CBF[UUID, Col]): Decoder[Col] =
arrayRawDecoder[UUID, Col]
}
Quill automatically encodes AnyVal
s (value classes):
case class UserId(value: Int) extends AnyVal
case class User(id: UserId, name: String)
val q = quote {
for {
u <- query[User] if u.id == lift(UserId(1))
} yield u
}
ctx.run(q)
// SELECT u.id, u.name FROM User u WHERE (u.id = 1)
The meta DSL allows the user to customize how Quill handles the expansion and execution of quotations through implicit meta instances.
By default, quill expands query[Person]
to querySchema[Person]("Person")
. It's possible to customize this behavior using an implicit instance of SchemaMeta
:
implicit val personSchemaMeta = schemaMeta[Person]("people", _.id -> "person_id")
ctx.run(query[Person])
// SELECT x.person_id, x.name, x.age FROM people x
InsertMeta
customizes the expansion of case classes for insert actions (query[Person].insert(p)
). By default, all columns are expanded and through an implicit InsertMeta
, it's possible to exclude columns from the expansion:
implicit val personInsertMeta = insertMeta[Person](_.id)
ctx.run(query[Person].insert(lift(Person(-1, "John", 22))))
// INSERT INTO Person (name,age) VALUES (?, ?)
Note that the parameter of insertMeta
is called exclude
, but it isn't possible to use named parameters for macro invocations.
UpdateMeta
customizes the expansion of case classes for update actions (query[Person].update(p)
). By default, all columns are expanded, and through an implicit UpdateMeta
, it's possible to exclude columns from the expansion:
implicit val personUpdateMeta = updateMeta[Person](_.id)
ctx.run(query[Person].filter(_.id == 1).update(lift(Person(1, "John", 22))))
// UPDATE Person SET name = ?, age = ? WHERE id = 1
Note that the parameter of updateMeta
is called exclude
, but it isn't possible to use named parameters for macro invocations.
This kind of meta instance customizes the expansion of query types and extraction of the final value. For instance, it's possible to use this feature to normalize values before reading them from the database:
implicit val personQueryMeta =
queryMeta(
(q: Query[Person]) =>
q.map(p => (p.id, infix"CONVERT(${p.name} USING utf8)".as[String], p.age))
) {
case (id, name, age) =>
Person(id, name, age)
}
The query meta definition is open and allows the user to even join values from other tables before reading the final value. This kind of usage is not encouraged.
Contexts represent the database and provide an execution interface for queries.
Quill provides mirror context for test purposes. Instead of running the query, mirror context return a structure with the information that would be used to run the query. There are three mirror context instances:
io.getquill.MirrorContext
: Mirrors the quotation ASTio.getquill.SqlMirrorContext
: Mirrors the SQL queryio.getquill.CassandraMirrorContext
: Mirrors the CQL query
The context instance provides all methods and types to interact with quotations and the database. Depending on how the context import happens, Scala won't be able to infer that the types are compatible.
For instance, this example will not compile:
class MyContext extends SqlMirrorContext(MirrorSqlDialect, Literal)
case class MySchema(c: MyContext) {
import c._
val people = quote {
querySchema[Person]("people")
}
}
case class MyDao(c: MyContext, schema: MySchema) {
def allPeople =
c.run(schema.people)
// ERROR: [T](quoted: MyDao.this.c.Quoted[MyDao.this.c.Query[T]])MyDao.this.c.QueryResult[T]
cannot be applied to (MyDao.this.schema.c.Quoted[MyDao.this.schema.c.EntityQuery[Person]]{def quoted: io.getquill.ast.ConfiguredEntity; def ast: io.getquill.ast.ConfiguredEntity; def id1854281249(): Unit; val bindings: Object})
}
One alternative to work with this kind of context import is use traits with abstract context values:
class MyContext extends SqlMirrorContext(MirrorSqlDialect, Literal)
trait MySchema {
val c: MyContext
import c._
val people = quote {
querySchema[Person]("people")
}
}
case class MyDao(c: MyContext) extends MySchema {
import c._
def allPeople =
c.run(people)
}
Quill provides a fully type-safe way to use Spark's highly-optimized SQL engine. It's an alternative to Dataset
's weakly-typed API.
libraryDependencies ++= Seq(
"io.getquill" %% "quill-spark" % "2.5.5-SNAPSHOT"
)
Differently from the other modules, the context is a companion object and doesn't depend on a spark session. To use it, add the following import:
import io.getquill.QuillSparkContext._
The spark session must be provided by the user through an implicit value:
import org.apache.spark.sql.SparkSession
// Replace by your spark sql context creation
implicit lazy val sqlContext =
SparkSession.builder().master("local").appName("spark test").getOrCreate().sqlContext
Quill decoders and meta instances are not used by the quill-spark module, Spark's Encoder
s are used instead. Add this import to have them in scope:
import sqlContext.implicits._
The liftQuery
method converts Dataset
s to Quill queries:
import org.apache.spark.sql.Dataset
def filter(myDataset: Dataset[Person], name: String): Dataset[Int] =
run {
liftQuery(myDataset).filter(_.name == lift(name)).map(_.age)
}
// SELECT x1.age _1 FROM (?) x1 WHERE x1.name = ?
Note that the run
method returns a Dataset
transformed by the Quill query using the SQL engine.
Additionally, note that the queries printed from run(myQuery)
during compile time escape question marks via a backslash them in order to
be able to substitute liftings properly. They are then returned back to their original form before running.
import org.apache.spark.sql.Dataset
run {
liftQuery(myDataset).filter(_.field == "?").map(_.anotherField)
}
// This is generated during compile time:
// SELECT x1.anotherField _1 FROM (?) x1 WHERE x1.field = '\?'
// It is reverted upon run-time:
// SELECT x1.anotherField _1 FROM (ds1) x1 WHERE x1.field = '?'
Important: Spark doesn't support transformations of inner classes. Use top-level classes.
Example:
lazy val ctx = new MysqlJdbcContext(SnakeCase, "ctx")
The SQL dialect parameter defines the specific database dialect to be used. Some context types are specific to a database and thus not require it.
Quill has five built-in dialects:
io.getquill.H2Dialect
io.getquill.MySQLDialect
io.getquill.PostgresDialect
io.getquill.SqliteDialect
io.getquill.SQLServerDialect
The naming strategy parameter defines the behavior when translating identifiers (table and column names) to SQL.
strategy | example |
---|---|
io.getquill.naming.Literal |
some_ident -> some_ident |
io.getquill.naming.Escape |
some_ident -> "some_ident" |
io.getquill.naming.UpperCase |
some_ident -> SOME_IDENT |
io.getquill.naming.LowerCase |
SOME_IDENT -> some_ident |
io.getquill.naming.SnakeCase |
someIdent -> some_ident |
io.getquill.naming.CamelCase |
some_ident -> someIdent |
io.getquill.naming.MysqlEscape |
some_ident -> `some_ident` |
io.getquill.naming.PostgresEscape |
$some_ident -> $some_ident |
Multiple transformations can be defined using NamingStrategy()
. For instance, the naming strategy
NamingStrategy(SnakeCase, UpperCase)
produces the following transformation:
someIdent -> SOME_IDENT
The transformations are applied from left to right.
The string passed to the context is used as the key to obtain configurations using the typesafe config library.
Additionally, the contexts provide multiple constructors. For instance, with JdbcContext
it's possible to specify a DataSource
directly, without using the configuration:
def createDataSource: javax.sql.DataSource with java.io.Closeable = ???
lazy val ctx = new MysqlJdbcContext(SnakeCase, createDataSource)
Quill uses HikariCP for connection pooling. Please refer to HikariCP's documentation for a detailed explanation of the available configurations.
Note that there are dataSource
configurations, that go under dataSource
, like user
and password
, but some pool settings may go under the root config, like connectionTimeout
.
The JdbcContext
provides thread-local transaction support:
ctx.transaction {
ctx.run(query[Person].delete)
// other transactional code
}
The body of transaction
can contain calls to other methods and multiple run
calls, since the transaction is propagated through a thread-local.
libraryDependencies ++= Seq(
"mysql" % "mysql-connector-java" % "5.1.38",
"io.getquill" %% "quill-jdbc" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new MysqlJdbcContext(SnakeCase, "ctx")
ctx.dataSourceClassName=com.mysql.jdbc.jdbc2.optional.MysqlDataSource
ctx.dataSource.url=jdbc:mysql://host/database
ctx.dataSource.user=root
ctx.dataSource.password=root
ctx.dataSource.cachePrepStmts=true
ctx.dataSource.prepStmtCacheSize=250
ctx.dataSource.prepStmtCacheSqlLimit=2048
ctx.connectionTimeout=30000
libraryDependencies ++= Seq(
"org.postgresql" % "postgresql" % "9.4.1208",
"io.getquill" %% "quill-jdbc" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new PostgresJdbcContext(SnakeCase, "ctx")
ctx.dataSourceClassName=org.postgresql.ds.PGSimpleDataSource
ctx.dataSource.user=root
ctx.dataSource.password=root
ctx.dataSource.databaseName=database
ctx.dataSource.portNumber=5432
ctx.dataSource.serverName=host
ctx.connectionTimeout=30000
libraryDependencies ++= Seq(
"org.xerial" % "sqlite-jdbc" % "3.18.0",
"io.getquill" %% "quill-jdbc" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new SqliteJdbcContext(SnakeCase, "ctx")
ctx.driverClassName=org.sqlite.JDBC
ctx.jdbcUrl=jdbc:sqlite:/path/to/db/file.db
libraryDependencies ++= Seq(
"com.h2database" % "h2" % "1.4.192",
"io.getquill" %% "quill-jdbc" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new H2JdbcContext(SnakeCase, "ctx")
ctx.dataSourceClassName=org.h2.jdbcx.JdbcDataSource
ctx.dataSource.url=jdbc:h2:mem:yourdbname
ctx.dataSource.user=sa
libraryDependencies ++= Seq(
"com.microsoft.sqlserver" % "mssql-jdbc" % "6.1.7.jre8-preview",
"io.getquill" %% "quill-jdbc" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new SqlServerJdbcContext(SnakeCase, "ctx")
ctx.dataSourceClassName=com.microsoft.sqlserver.jdbc.SQLServerDataSource
ctx.dataSource.user=user
ctx.dataSource.password=YourStrongPassword
ctx.dataSource.databaseName=database
ctx.dataSource.portNumber=1433
ctx.dataSource.serverName=host
The async module provides transaction support based on a custom implicit execution context:
ctx.transaction { implicit ec =>
ctx.run(query[Person].delete)
// other transactional code
}
The body of transaction
can contain calls to other methods and multiple run
calls, but the transactional code must be done using the provided implicit execution context. For instance:
def deletePerson(name: String)(implicit ec: ExecutionContext) =
ctx.run(query[Person].filter(_.name == lift(name)).delete)
ctx.transaction { implicit ec =>
deletePerson("John")
}
Depending on how the main execution context is imported, it is possible to produce an ambigous implicit resolution. A way to solve this problem is shadowing the multiple implicits by using the same name:
import scala.concurrent.ExecutionContext.Implicits.{ global => ec }
def deletePerson(name: String)(implicit ec: ExecutionContext) =
ctx.run(query[Person].filter(_.name == lift(name)).delete)
ctx.transaction { implicit ec =>
deletePerson("John")
}
Note that the global execution context is renamed to ec.
ctx.host=host
ctx.port=1234
ctx.user=root
ctx.password=root
ctx.database=database
or use connection URL with database-specific scheme (see below):
ctx.url=scheme://host:5432/database?user=root&password=root
ctx.poolMaxQueueSize=4
ctx.poolMaxObjects=4
ctx.poolMaxIdle=999999999
ctx.poolValidationInterval=10000
Also see PoolConfiguration
documentation.
ctx.sslmode=disable # optional, one of [disable|prefer|require|verify-ca|verify-full]
ctx.sslrootcert=./path/to/cert/file # optional, required for sslmode=verify-ca or verify-full
ctx.charset=UTF-8
ctx.maximumMessageSize=16777216
ctx.connectTimeout=5s
ctx.testTimeout=5s
ctx.queryTimeout=10m
libraryDependencies ++= Seq(
"io.getquill" %% "quill-async-mysql" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new MysqlAsyncContext(SnakeCase, "ctx")
See above
For url
property use mysql
scheme:
ctx.url=mysql://host:3306/database?user=root&password=root
libraryDependencies ++= Seq(
"io.getquill" %% "quill-async-postgres" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new PostgresAsyncContext(SnakeCase, "ctx")
For url
property use postgresql
scheme:
ctx.url=postgresql://host:5432/database?user=root&password=root
The finagle context provides transaction support through a Local
value. See twitter util's scaladoc for more details.
ctx.transaction {
ctx.run(query[Person].delete)
// other transactional code
}
The body of transaction
can contain calls to other methods and multiple run
calls, since the transaction is automatically propagated through the Local
value.
libraryDependencies ++= Seq(
"io.getquill" %% "quill-finagle-mysql" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new FinagleMysqlContext(SnakeCase, "ctx")
ctx.dest=localhost:3306
ctx.user=root
ctx.password=root
ctx.database=database
ctx.pool.watermark.low=0
ctx.pool.watermark.high=10
ctx.pool.idleTime=5 # seconds
ctx.pool.bufferSize=0
ctx.pool.maxWaiters=2147483647
The finagle context provides transaction support through a Local
value. See twitter util's scaladoc for more details.
ctx.transaction {
ctx.run(query[Person].delete)
// other transactional code
}
The body of transaction
can contain calls to other methods and multiple run
calls, since the transaction is automatically propagated through the Local
value.
libraryDependencies ++= Seq(
"io.getquill" %% "quill-finagle-postgres" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new FinaglePostgresContext(SnakeCase, "ctx")
ctx.host=localhost:3306
ctx.user=root
ctx.password=root
ctx.database=database
ctx.useSsl=false
ctx.hostConnectionLimit=1
ctx.numRetries=4
ctx.binaryResults=false
ctx.binaryParams=false
libraryDependencies ++= Seq(
"io.getquill" %% "quill-cassandra" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new CassandraSyncContext(SnakeCase, "ctx")
lazy val ctx = new CassandraAsyncContext(SnakeCase, "ctx")
lazy val ctx = new CassandraStreamContext(SnakeCase, "ctx")
The configurations are set using runtime reflection on the Cluster.builder
instance. It is possible to set nested structures like queryOptions.consistencyLevel
, use enum values like LOCAL_QUORUM
, and set multiple parameters like in credentials
.
ctx.keyspace=quill_test
ctx.preparedStatementCacheSize=1000
ctx.session.contactPoint=127.0.0.1
ctx.session.withPort=9042
ctx.session.queryOptions.consistencyLevel=LOCAL_QUORUM
ctx.session.withoutMetrics=true
ctx.session.withoutJMXReporting=false
ctx.session.credentials.0=root
ctx.session.credentials.1=pass
ctx.session.maxSchemaAgreementWaitSeconds=1
ctx.session.addressTranslator=com.datastax.driver.core.policies.IdentityTranslator
libraryDependencies ++= Seq(
"io.getquill" %% "quill-orientdb" % "2.5.5-SNAPSHOT"
)
lazy val ctx = new OrientDBSyncContext(SnakeCase, "ctx")
The configurations are set using OPartitionedDatabasePool
which creates a pool of DB connections from which an instance of connection can be acquired. It is possible to set DB credentials using the parameter called username
and password
.
ctx.dbUrl=remote:127.0.0.1:2424/GratefulDeadConcerts
ctx.username=root
ctx.password=root
To disable logging of queries during compilation use quill.macro.log
option:
sbt -Dquill.macro.log=false
Quill uses SLF4J for logging. Each context logs queries which are currently executed.
It also logs the list of parameters which are bound into prepared statement if any.
To enable that use quill.binds.log
option:
java -Dquill.binds.log=true -jar myapp.jar
In order to quickly start with Quill, we have setup some template projects:
Please refer to SLICK.md for a detailed comparison between Quill and Slick.
Please refer to CASSANDRA.md for a detailed comparison between Quill and other main alternatives for interaction with Cassandra in Scala.
- scala-db-codegen - Code/boilerplate generator from db schema
- quill-cache - Caching layer for Quill
- quill-gen - a DAO generator for
quill-cache
ScalaDays Berlin 2016 - Scylla, Charybdis, and the mystery of Quill
quill-spark: A type-safe Scala API for Spark SQL Scalac.io blog - Compile-time Queries with Quill
Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms. See CODE_OF_CONDUCT.md for details.
See the LICENSE file for details.
- @fwbrasil (creator)
- @deusaquilus
- @jilen
- @mentegy
- @mxl
- @gustavoamigo
- @godenji
- @lvicentesanchez
You can notify all current maintainers using the handle @getquill/maintainers
.
The project was created having Philip Wadler's talk "A practical theory of language-integrated query" as its initial inspiration. The development was heavily influenced by the following papers: