ColumnDefinition

public final class ColumnDefinition

The ColumnDefinition class lets you refine a table column.

You get instances of this class when you create or alter a database table:

try db.create(table: "player") { t in
    t.column(...)      // ColumnDefinition
}

try db.alter(table: "player") { t in
    t.add(column: ...) // ColumnDefinition
}

See https://www.sqlite.org/lang_createtable.html and https://www.sqlite.org/lang_altertable.html


                    
                    
                    primaryKey(onConflict:autoincrement:)

Adds a primary key constraint on the column.

try db.create(table: "player") { t in
    t.column("id", .integer).primaryKey()
}

See https://www.sqlite.org/lang_createtable.html#primkeyconst and https://www.sqlite.org/lang_createtable.html#rowid

Declaration

Swift

@discardableResult
public func primaryKey(
    onConflict conflictResolution: Database.ConflictResolution? = nil,
    autoincrement: Bool = false)
    -> Self

Parameters

`conflictResolution`	An optional conflict resolution (see https://www.sqlite.org/lang_conflict.html).
`autoincrement`	If true, the primary key is autoincremented.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    notNull(onConflict:)

Adds a NOT NULL constraint on the column.

try db.create(table: "player") { t in
    t.column("name", .text).notNull()
}

See https://www.sqlite.org/lang_createtable.html#notnullconst

Declaration

Swift

@discardableResult
public func notNull(onConflict conflictResolution: Database.ConflictResolution? = nil) -> Self

Parameters


                                conflictResolution

An optional conflict resolution (see https://www.sqlite.org/lang_conflict.html).

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    unique(onConflict:)

Adds a UNIQUE constraint on the column.

try db.create(table: "player") { t in
    t.column("email", .text).unique()
}

See https://www.sqlite.org/lang_createtable.html#uniqueconst

Declaration

Swift

@discardableResult
public func unique(onConflict conflictResolution: Database.ConflictResolution? = nil) -> Self

Parameters


                                conflictResolution

An optional conflict resolution (see https://www.sqlite.org/lang_conflict.html).

Return Value

Self so that you can further refine the column definition.

Show on GitHub

indexed()
Adds an index of the column.
```
try db.create(table: "player") { t in
    t.column("email", .text).indexed()
}
```
See https://www.sqlite.org/lang_createtable.html#uniqueconst
Declaration
Swift

@discardableResult public func indexed() -> Self
Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    check(_:)

Adds a CHECK constraint on the column.

try db.create(table: "player") { t in
    t.column("name", .text).check { length($0) > 0 }
}

See https://www.sqlite.org/lang_createtable.html#ckconst

Declaration

Swift

@discardableResult
public func check(_ condition: (Column) -> SQLExpressible) -> Self

Parameters


                                condition

A closure whose argument is an Column that represents the defined column, and returns the expression to check.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    check(sql:)

Adds a CHECK constraint on the column.

try db.create(table: "player") { t in
    t.column("name", .text).check(sql: "LENGTH(name) > 0")
}

See https://www.sqlite.org/lang_createtable.html#ckconst

Declaration

Swift

@discardableResult
public func check(sql: String) -> Self

Parameters

sql

An SQL snippet.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    defaults(to:)

Defines the default column value.

try db.create(table: "player") { t in
    t.column("name", .text).defaults(to: "Anonymous")
}

See https://www.sqlite.org/lang_createtable.html#dfltval

Declaration

Swift

@discardableResult
public func defaults(to value: DatabaseValueConvertible) -> Self

Parameters


                                value

A DatabaseValueConvertible value.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    defaults(sql:)

Defines the default column value.

try db.create(table: "player") { t in
    t.column("creationDate", .DateTime).defaults(sql: "CURRENT_TIMESTAMP")
}

See https://www.sqlite.org/lang_createtable.html#dfltval

Declaration

Swift

@discardableResult
public func defaults(sql: String) -> Self

Parameters

sql

An SQL snippet.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    collate(_:)

try db.create(table: "player") { t in
    t.column("email", .text).collate(.nocase)
}

See https://www.sqlite.org/datatype3.html#collation

Declaration

Swift

@discardableResult
public func collate(_ collation: Database.CollationName) -> Self

Parameters


                                collation

An Database.CollationName.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    collate(_:)

try db.create(table: "player") { t in
    t.column("name", .text).collate(.localizedCaseInsensitiveCompare)
}

See https://www.sqlite.org/datatype3.html#collation

Declaration

Swift

@discardableResult
public func collate(_ collation: DatabaseCollation) -> Self

Parameters


                                collation

A custom DatabaseCollation.

Return Value

Self so that you can further refine the column definition.

Show on GitHub


                    
                    
                    references(_:column:onDelete:onUpdate:deferred:)

Defines a foreign key.

try db.create(table: "book") { t in
    t.column("authorId", .integer).references("author", onDelete: .cascade)
}

See https://www.sqlite.org/foreignkeys.html

Declaration

Swift

@discardableResult
public func references(
    _ table: String,
    column: String? = nil,
    onDelete deleteAction: Database.ForeignKeyAction? = nil,
    onUpdate updateAction: Database.ForeignKeyAction? = nil,
    deferred: Bool = false) -> Self

Return Value

Self so that you can further refine the column definition.

Show on GitHub