How to create Autoincrement column in SQLite using EF core?

I just ran into this with a SQLite in memory database I was using for testing. In my case I had a business class with a primary key field called ContactCategoryId:

public class ContactCategory
{
    [Required]
    [Display(Name = "Contact category ID")]
    public int ContactCategoryId { get; set; }

And I was also using the fluent approach for the settings:

public void Configure(EntityTypeBuilder<ContactCategory> modelBuilder)
{
    modelBuilder.ToTable("CONTACT_CATEGORY", _schema);

    modelBuilder.HasKey(x => x.ContactCategoryId);

    modelBuilder.Property(x => x.ContactCategoryId)
        .HasColumnName(@"ContactCategoryID")
        //.HasColumnType("int") Weirdly this was upsetting SQLite
        .IsRequired()
        .ValueGeneratedOnAdd()
        ;

Commenting out the line for .HasColumnType("int") fixed the error for me.

My model has an entity of type Primary Key integer which should be served as auto increment

The problem is that the property in question is not a PK, but a part of a composite PK, in which case it's not considered as auto generated by convention, as explained in the Generated Values Conventions section of the EF Core documentation:

By convention, non-composite primary keys of type short, int, long, or Guid will be setup to have values generated on add. All other properties will be setup with no value generation.

You need to specify that explicitly:

modelBuilder.Entity<TurnosGeneral>()
    .Property(e => e.No)
    .ValueGeneratedOnAdd();

Update: The above is the general approach applicable for most of the databases. But SQLite supports AutoIncrement only for column of type INTEGER PRIMARY KEY, hence this is not EF Core limitation. Either don't use auto increment or make it non-composite PK.