https://github.com/jacentino/typesafesql

Linq-like SQL query builder for use with microORMs.
https://github.com/jacentino/typesafesql

c-sharp dapper linq sql-query

Last synced: 10 months ago
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Linq-like SQL query builder for use with microORMs.

• Host: GitHub
• URL: https://github.com/jacentino/typesafesql
• Owner: jacentino
• License: gpl-2.0
• Created: 2014-03-04T22:18:06.000Z (almost 12 years ago)
• Default Branch: master
• Last Pushed: 2014-03-09T22:43:07.000Z (almost 12 years ago)
• Last Synced: 2025-04-07T15:01:33.451Z (11 months ago)
• Topics: c-sharp, dapper, linq, sql-query
• Language: C#
• Homepage:
• Size: 598 KB
• Stars: 12
• Watchers: 4
• Forks: 2
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
TypesafeSQL

===========

Linq-like SQL query builder for use with micro ORMs.

The purpose of TypesafeSQL is to allow for generate SQL queries in typesafe way, thus it's not a real Linq provider to relational database. It provides familiar linq syntax to express queries, but doesn't implement IQueryable. 

Features

--------

* select, where, order by

* inner joins, 

* outer joins (not available with SQL-like syntax)

* group by

* count, sum, avg (only available in queries with group by)

* union, intersect, except

* almost all MS SQL functions

* subqueries (when defined outside a main query)

* easy integration with [Dapper.NET](http://code.google.com/p/dapper-dot-net/)

* mapping class names to table names and property names to column names with name resolvers

Supported databases

-------------------

For now, only MS SQL 2012 is supported. Future releases will support MySQL, PostgreSQL and SQLite.

Examples

--------

Simple SQL command generation:

    var builder = new QueryBuilder();

    var query = from u in builder.Table() where u.LoginAttempts >= 3 select u;

    var sql = query.ToSql();

Retrieving data with Dapper:

    var connection = new SqlConnection();

    var builder = new QueryBuilder();

    var users = connection.Query(from u in builder.Table() where u.LoginAttempts >= 3 select u);

    

Inner joins:

    var builder = new QueryBuilder();

    var roles = from user in builder.Table()

                join link in builder.Table() on user.Id equals link.UserId

                join role in builder.Table() on link.RoleId equals role.Id

                select new { user.Login, Role = role.Name };

Outer joins:

    var builder = new QueryBuilder();

    var roles = builder.Table()

        .LeftJoin(builder.Table(), user => user.Id, link => link.UserId, (user, link) => new { user, link })

        .LeftJoin(builder.Table(), ul => ul.link.RoleId, role => role.Id, (ul, role) => new { ul, role })

        .Select(ulr => new { ulr.ul.user.Login, ulr.role.Name });

Group by:

    var builder = new QueryBuilder();

    var roleCounts = from l in builder.Table()

                     group l by l.UserId into lg

                     select new { UserId = lg.Key, NumOfRoles = lg.Count(x => x.RoleId) };

Using name resolvers:

        public class PrefixBasedNameResolver : DefaultNameResolver

        {

            public override string ResolveTableName(Type modelClass)

            {

                return "tbl_" + base.ResolveTableName(modelClass);

            }

            

            public override string ResolveColumnName(System.Reflection.MemberInfo property)

            {

                return "col_" + base.ResolveColumnName(property);

            }

        }

        ...

        var builder = new QueryBuilder(new PrefixBasedNameResolver());

        ...