Linq

The LINQ system, which allows you to write SQL-like queries, can be used naturally in AventusSharp.

Example: LINQ Query on a User

var users = User.Where(u => u.Name == "John");

However, there are some restrictions on the functions that can be used in LINQ queries. The following functions are supported:

Supported LINQ Functions

String Functions

You can use the following string functions in LINQ queries:

• StartsWith
• Contains
• EndsWith
• ToLower
• ToUpper

Example:

var result = User.Where(u => u.Name.StartsWith("John"));

DateTime Functions

For DateTime or Datetime or Date types, you can use the following properties:

• Year
• Month
• Day
• Hour
• Minute
• Second

Example:

var result = User.Where(u => u.CreatedAt.Year == 2024);

List Functions

You can use Contains with lists of simple types like int, decimal, double, float, string, bool, DateTime, or Date.

• List<int>
• List<decimal>
• List<double>
• List<float>
• List<string>
• List<bool>
• List<DateTime>
• List<Date>

Example (for a list of integers):

List<int> ids = new List<int>() { 1, 2 };
var result = User.Where(u => ids.Contains(u.Id));

List of Storable

For lists of objects that implement the Storable interface, you can use Contains as well.

Example (for a list of tags):

var result = User.Where(u => u.Tags.Contains(new Tag { Id = 1 }));

Debugging SQL Queries

If the generated SQL queries don’t seem correct, you can set the Debug boolean to true on your MySQLStorage object. This will enable query logging, allowing you to see the SQL queries being executed against the database.

This feature can help you troubleshoot issues by providing the exact SQL query, which you can then use when opening an issue. Make sure to include both the source code and the SQL result when reporting the problem.

// storage is MySQLStorage
Aventus.storage.Debug = true;

Once enabled, all the SQL queries generated by your LINQ operations will be displayed, making it easier to track down potential issues.

Conclusion

LINQ in AventusSharp allows you to query objects using common functions, but it has some limitations. Make sure to use only the supported functions listed above when writing your queries.