/query-builder

A humble but eloquent builder for sql query strings in C#/.NET

Primary LanguageC#

QueryBuilder

A humble but hopefully eloquent query builder for C#/.Net. Primary purpose is building SQL query statements from idiomatic C# code.

Example

Build conditions with code

The following definition

var t = new ColumnSelector();
var condition =
      t["col1", table: "other"] == t["col2"] && t["col3"] != 3 ||
      5 == t["col2"] && t["post_id"].References("post");

Console.WriteLine(condition);

generates

((other.col1 = col2 AND col3 != 3) OR (5 = col2 AND post_id = post.ID))

Patterns and tools used

  • Composite pattern to build an object graph representing a SQL-like query structure
  • Operator Overloading
  • Builder pattern, kind of
  • Visitor pattern for implementing Sql (and any other) representations. Some research will be needed on my part to get to a satisfying solution here.

Overview

classDiagram

Query --> Condition: where
Query *-- FromDefinition: from
Query *-- JoinDefinition: join
Query *-- ColumnDefinition: select
Query *-- OrderDefinition: order
Query *-- LimitDefinition: limit

JoinDefinition --> Condition: on
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