Ef core 5 many to many filter

问题

This is my query

 public async Task<IEnumerable<Menu>> GetMenuByRolesAsync(string[] roles)
        {
    var result= await _context.Menus//.Include(o => o.Parent)
                                     .Include(m => m.Childrens)
                                     .ThenInclude(m => m.Childrens)
                                     .Include(m => m.Roles.Where(r => roles.Contains(r.Name)))   --it is not filtering basd on roles                          
                                     .Where(m => m.ParentId == null)
                                     .ToListAsync();
}

It is generating below query

-- @__roles_0='System.String[]' (DbType = Object)
SELECT m.id, m.icon, m.name, m.parent_id, m.url, t.role_id, t.menu_id, t.id, t.concurrency_stamp, t.name, t.normalized_name
FROM security.menu AS m
LEFT JOIN (
    SELECT r.role_id, r.menu_id, r0.id, r0.concurrency_stamp, r0.name, r0.normalized_name
    FROM security.role_menu AS r
    INNER JOIN security.role AS r0 ON r.role_id = r0.id
    WHERE r0.name = ANY (@__roles_0) OR ((r0.name IS NULL) AND (array_position(@__roles_0, NULL) IS NOT NULL))
) AS t ON m.id = t.menu_id
WHERE (m.parent_id IS NULL)
ORDER BY m.id, t.role_id, t.menu_id, t.id

This is Many to many configuration // many to many

    builder.HasMany(r => r.Menus)
           .WithMany(r => r.Roles)
           .UsingEntity<RoleMenu>(
              j => j
                  .HasOne(rm => rm.Menu)
                  .WithMany(m => m.RoleMenus)
                  .HasForeignKey(rm => rm.MenuId),
              j => j
                  .HasOne(rm => rm.Role)
                  .WithMany(r => r.RoleMenus)
                  .HasForeignKey(rm => rm.RoleId),
              j =>
              {
                  j.ToTable("role_menu", schema: "security");                                                 
                  j.HasKey(rm => new { rm.RoleId, rm.MenuId });
              });

i need to filter menus based on roles..But it is not filtering based on roles..Am getting all the roles..I checked generated query..Please let me know what is the issue..

回答1:

You are mixing filtered include with entity filtering.

Filtered include

.Include(m => m.Roles.Where(r => roles.Contains(r.Name)))

just filters the items in the related collection (menu roles in this case).

In order to filter the entity set (menus in this case), you need to replace it with the usual Where oparator, which for the desired filtering will be

.Where(m => m.Roles.Any(r => roles.Contains(r.Name)))

来源：https://stackoverflow.com/questions/65804252/ef-core-5-many-to-many-filter

标签

postgresql

asp.net-core

entity-framework-core