Sequel 3.1.4

Sequel

一个高效的 SQL 构建器，具有模拟实际 SQL 查询编写的接口。

入门指南

SELECT

var sqlBuilder = new SqlBuilder()
  .Select("Id", "Salary")
  .From("dbo.Test");

var sql = sqlBuilder.ToSql(); // .ToString() also works

/*
SELECT Id, Salary FROM dbo.Test
*/

// SELECT with INNER & LEFT JOIN
var sqlBuilder = new SqlBuilder()
  .Select("*")
  .From("dbo.Test t")
  .Join("dbo.Employee e on e.Id = t.EmployeeId")
  .LeftJoin("dbo.Manager m on m.Id = e.ManagerId");

var sql = sqlBuilder.ToSql();

/*
SELECT * FROM dbo.Test t INNER JOIN dbo.Employee e on e.Id = t.EmployeeId LEFT JOIN dbo.Manager m on m.Id = e.ManagerId
*/

INSERT

var sqlBuilder = new SqlBuilder()
  .Insert("dbo.Test")
  .Columns("Name", "Salary")
  .Values("'John'", "50")
  .Values("'Jane'", "100");

var sql = sqlBuilder.ToSql(); // .ToString() also works

/*
INSERT INTO dbo.Test (Name, Salary) VALUES ('John', 50), ('Jane', 100)
*/

UPDATE

var sqlBuilder = new SqlBuilder()
  .Update("dbo.Test")
  .Set("Salary = 100", "ManagerId = 2")
  .Where("EmployeeId = 1");

var sql = sqlBuilder.ToSql(); // .ToString() also works

/*
UPDATE dbo.Test SET Salary = 100, ManagerId = 2 WHERE EmployeeId = 1
*/

DELETE

var sqlBuilder = new SqlBuilder()
  .Delete()
  .From("dbo.Test")
  .Where("EmployeeId = 1");

var sql = sqlBuilder.ToSql(); // .ToString() also works

/*
DELETE FROM dbo.Test WHERE EmployeeId = 1
*/

注入自定义 SQL

您被授予预挂钩和后挂钩直接访问最终 SQL 字符串，以便注入自定义 SQL。

预挂钩在 CTE 或内联声明的情况下很有用。

var sqlBuilder = new SqlBuilder(pre: "WITH cte AS (SELECT 1) ")
  .Select("*")
  .From("cte");

var sql = sqlBuilder.ToSql();

/*
WITH cte AS (SELECT 1) SELECT * FROM cte"
*/

后挂钩在需要获取最近插入的行标识符等情况下很有用。

var sqlBuilder = new SqlBuilder(post: "; SELECT last_insert_rowid();")
  .Insert("dbo.Test")
  .Into("Name", "Salary")
  .Value("'Pim'", "50");

var sql = sqlBuilder.ToSql();

/*
INSERT INTO dbo.Test (Name, Salary) VALUES ('Pim', 50); SELECT last_insert_rowid();
*/

示例使用 Dapper

using(var conn = new SqlConnection("your connection string")
{
  var sqlBuilder = new SqlBuilder()
    .Select("Id", "Salary")
    .From("dbo.Test")
    .Where("Id", "@Id");

  var sql = sqlBuilder.ToSql(); // .ToString() also works
  /*
  SELECT Id, Salary FROM dbo.Test WHERE Id = @Id
  */

  var result = conn.Query(sql, new { Id = 1 });
}

发现虫子了？

为此有 一个问题。

许可协议

由 NHLPA 工程师 在安大略省多伦多用爱心构建。遵循 MIT 许可协议。