+SqlBind.CSharp
+
+SqlBind.CSharp is a C# class library that is a wrapper for SQLite.
+How to create a table and insert rows
+Let's consider creating the Actors table as follows:
+
+Actors
+
+
+
+id |
+name |
+
+
+
+
+1 |
+Chloë Grace Moretz |
+
+
+2 |
+Gary Carr |
+
+
+3 |
+Jack Reynor |
+
+
+
+
+Create the following class to represent this table:
+[Table("Actors")]
+public record class Actor(
+ [Column("id")][PrimaryKey][AutoIncrement] long Id,
+ [Column("name")] string Name)
+{
+}
+
+Each parameter in the constructor of the Actor
class corresponds to each column in the Actors table in the same order. The type of each parameter must be either long
or string
.
+Note that you can implement the Actor
class without a record
class. However, the parameter names of the constructor must start with an uppercase letter if you create a regular one according to the naming conventions of the record
class. This is inconsistent with general naming conventions. Therefore, we recommend that you use record
classes.
+The following code from the Example
class uses the Actor
class to create the Actors table and add three rows of data to the table:
+public sealed class Example
+{
+ private TransactionKit Kit { get; } = new TransactionKit(
+ "example.db",
+ m => Console.WriteLine(m()));
+
+ public void CreateTableAndInsertRows()
+ {
+ Kit.Execute(q =>
+ {
+ q.NewTables(typeof(Actor));
+ q.Insert(new Actor(0, "Chloë Grace Moretz"));
+ q.Insert(new Actor(0, "Gary Carr"));
+ q.Insert(new Actor(0, "Jack Reynor"));
+ });
+ }
+ ...
+
+The Kit
property has the TransactionKit
instance, which uses the example.db
file as a database backend and writes log messages to the console. The Execute
method executes the queries that the lambda expression of its parameter performs atomically (as a single transaction).
+Note that calling the Insert(object)
method with the Actor
instance ignores its Id
property, which is specified with the first parameter of the constructor of the Actor
class, because it is qualified with the AutoIncrement
attribute.
+The log messages that the CreateTableAndInsertRows()
method prints to the console are as follows:
+DROP TABLE IF EXISTS Actors
+CREATE TABLE Actors (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Chloë Grace Moretz)
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Gary Carr)
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Jack Reynor)
+
+The non-indented lines are actual SQL statements that were automatically generated and executed.
+How to select a table and get rows
+Then run the SelectAllRows()
method as follows:
+public sealed class Example
+{
+ ...
+ public void SelectAllRows()
+ {
+ Kit.Execute(q =>
+ {
+ var all = q.SelectAll<Actor>();
+ foreach (var i in all)
+ {
+ Console.WriteLine(i);
+ }
+ });
+ }
+ ...
+
+The SelectAllRows()
method outputs:
+SELECT id, name FROM Actors
+Actor { Id = 1, Name = Chloë Grace Moretz }
+Actor { Id = 2, Name = Gary Carr }
+Actor { Id = 3, Name = Jack Reynor }
+
+The first line is the log message that the TransactionKit
instance prints. The SelectAll<T>()
method generates this statement.
+The next three lines are the messages that the WriteLine(object)
method outputs within the foreach
block.
+Inner join with two or more tables
+Consider the following Titles table:
+
+Titles
+
+
+
+id |
+name |
+
+
+
+
+1 |
+Peripheral |
+
+
+
+
+And the following Casts table:
+
+Casts
+
+
+
+id |
+titleId |
+actorId |
+role |
+
+
+
+
+1 |
+1 |
+1 |
+Flynne Fisher |
+
+
+2 |
+1 |
+2 |
+Wilf Netherton |
+
+
+3 |
+1 |
+3 |
+Burton Fisher |
+
+
+
+
+The classes that correspond to these tables are:
+[Table("Titles")]
+public record class Title(
+ [Column("id")][PrimaryKey][AutoIncrement] long Id,
+ [Column("name")] string Name)
+{
+}
+
+[Table("Casts")]
+public record class Cast(
+ [Column("id")][PrimaryKey][AutoIncrement] long Id,
+ [Column("titleId")] long TitleId,
+ [Column("actorId")] long ActorId,
+ [Column("role")] string Role)
+{
+}
+
+The following code creates the tables and inserts the rows:
+public sealed class Example
+{
+ ...
+ public void CreateTables()
+ {
+ Kit.Execute(q =>
+ {
+ q.NewTables(typeof(Title));
+ q.NewTables(typeof(Actor));
+ q.NewTables(typeof(Cast));
+ var titleId = q.InsertAndGetRowId(new Title(0, "Peripheral"));
+ var allCasts = new (string Name, string Role)[]
+ {
+ ("Chloë Grace Moretz", "Flynne Fisher"),
+ ("Gary Carr", "Wilf Netherton"),
+ ("Jack Reynor", "Burton Fisher"),
+ };
+ foreach (var (name, role) in allCasts)
+ {
+ var actorId = q.InsertAndGetRowId(new Actor(0, name));
+ q.Insert(new Cast(0, titleId, actorId, role));
+ }
+ });
+ }
+ ...
+
+The log messages that the CreateTables()
method prints to the console are as follows:
+DROP TABLE IF EXISTS Titles
+CREATE TABLE Titles (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)
+DROP TABLE IF EXISTS Actors
+CREATE TABLE Actors (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)
+DROP TABLE IF EXISTS Casts
+CREATE TABLE Casts (id INTEGER PRIMARY KEY AUTOINCREMENT, titleId INTEGER, actorId INTEGER, role TEXT)
+INSERT INTO Titles (name) VALUES ($name)
+ ($name, Peripheral)
+select last_insert_rowid()
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Chloë Grace Moretz)
+select last_insert_rowid()
+INSERT INTO Casts (titleId, actorId, role) VALUES ($titleId, $actorId, $role)
+ ($titleId, 1)
+ ($role, Flynne Fisher)
+ ($actorId, 1)
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Gary Carr)
+select last_insert_rowid()
+INSERT INTO Casts (titleId, actorId, role) VALUES ($titleId, $actorId, $role)
+ ($titleId, 1)
+ ($role, Wilf Netherton)
+ ($actorId, 2)
+INSERT INTO Actors (name) VALUES ($name)
+ ($name, Jack Reynor)
+select last_insert_rowid()
+INSERT INTO Casts (titleId, actorId, role) VALUES ($titleId, $actorId, $role)
+ ($titleId, 1)
+ ($role, Burton Fisher)
+ ($actorId, 3)
+
+Let's suppose that you would like to get a list of the names of the actors who performed in the specified title. To do this, use the APIs as follows:
+public sealed class Example
+{
+ ...
+ public void ListActorNames(string title)
+ {
+ Kit.Execute(q =>
+ {
+ var map = new Dictionary<string, object>
+ {
+ ["$name"] = title,
+ };
+ var all = q.SelectAllFrom<Actor>("a")
+ .InnerJoin<Cast>("c", "a.id = c.actorId")
+ .InnerJoin<Title>("t", "t.id = c.titleId")
+ .Where("t.name = $name", map)
+ .Execute();
+ foreach (var i in all)
+ {
+ Console.WriteLine(i.Name);
+ }
+ });
+ }
+ ...
+
+
+Calling ListActorNames("Peripheral");
results in the following output:
+SELECT a.id, a.name FROM Actors a INNER JOIN Casts c ON a.id = c.actorId INNER JOIN Titles t ON t.id = c.titleId WHERE t.name = $name
+ ($name, Peripheral)
+Chloë Grace Moretz
+Gary Carr
+Jack Reynor
+
+Get started
+SqlBind.CSharp is available as
+the NuGet package.
+API Reference
+
+
+