Is possible to use Npgsql and Entity Framework 6 for query PostgreSQL ignoring accents? In play SQL it's possible to use the unaccent extension and could be indexed with a index also based in unaccent:
select * from users where unaccent(name) = unaccent('João')
In previous projects using MySql I could solve this problem just using a collation accent insensitive like utf8_swedish_ci but PostgreSQL lacks this kind of solution as far as I know.
If you use the Codefirst approach, you should try to use EntityFramework.CodeFirstStoreFunctions.
Example of database context:
public class DatabaseContext : DbContext
{
public DatabaseContext () : base("Context")
{
Database.SetInitializer<DatabaseContext>(null);
}
public DbSet<User> Users { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.HasDefaultSchema("public");
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
/** Adding unaccent **/
modelBuilder.Conventions.Add(new CodeFirstStoreFunctions.FunctionsConvention<DatabaseContext>("public"));
}
[DbFunction("CodeFirstDatabaseSchema", "unaccent")]
public string Unaccent(string value)
{
// no need to provide an implementation
throw new NotSupportedException();
}
}
Example of usage:
var users = ctx.Users
.Where(elem => ctx.Unaccent(elem.FirstName) == ctx.Unaccent("João"))
.ToList();
Important notice:
This solution works with EntityFramework6.Npgsql (which uses Npgsql 3.*).
It doesn't work with Npgsql.EntityFramework (which uses Npgsql 2.*)
Net6 this work for me
.Where(x => people.ILike(EF.Functions.Unaccent(x.Name)....
