Devart Forums

Code: Select all

using (MyDataContext ctxt = new MyDataContext(conn))
{
  IQueryable entities =
     from e in ctxt.MyEntities
     orderby e.IdEntity
     select e;

  Console.WriteLine("{0} entities.", entities.Count());
  int i = 0;

  foreach (MyEntity e in entities)
  {
    Console.WriteLine("{0} - {1}", i++, e.IdEntity);
  }
}

Code: Select all

CREATE TABLE MyEntity
(
    idEntity SERIAL PRIMARY KEY
)
WITHOUT OIDS;

CREATE TABLE MyEntityVersion
(
    idEntity INT NOT NULL
        REFERENCES MyEntity (idEntity )
	    ON DELETE CASCADE,
    nVersion INT NOT NULL DEFAULT 1,
    PRIMARY KEY (idEntity , nVersion),

    name VARCHAR(20),
    ...
)
WITHOUT OIDS;

Code: Select all

using (MyDataContext ctxt = new MyDataContext(conn)) 
{ 
  IQueryable entities = 
     from e in ctxt.MyEntityVersions
     orderby e.IdEntity 
     select e; 

  int count = entities.Count();

  List list = entities.ToList();

  if (list.Count < count)
  {
      list = (from e in ctxt.MyEntityVersions
               orderby e.IdEntity
               select e).ToList();
  }
}

Code: Select all

[Column(Name = @"IdEntity", Storage = "_IdEntity", CanBeNull = false, DbType = "int4 NOT NULL", IsPrimaryKey = true)]
public int IdEntity
...

[Column(Name = @"nVersion", Storage = "_NVersion", CanBeNull = false, DbType = "int4 NOT NULL", IsPrimaryKey = true)]
        public int NVersion
...

Code: Select all

[Column(Name = @"IdEntity", Storage = "_IdEntity", AutoSync = AutoSync.OnInsert, CanBeNull = false, DbType = "serial NOT NULL AUTO_INCREMENT", IsDbGenerated = true, IsPrimaryKey = "true")]
        public int IdEntity

Code: Select all

CREATE TABLE abc (
ida INT NOT NULL REFERENCES A (ida) ON DELETE CASCADE,
idb INT NOT NULL REFERENCES B (ida) ON DELETE CASCADE,
seq INT NOT NULL,
PRIMARY KEY (ida, idb, seq),
x REAL ARRAY,
n INT)
WITHOUT OIDS;

Code: Select all

CREATE TABLE A (ida SERIAL PRIMARY KEY, ...) WITHOUT OIDS;
CREATE TABLE B (
ida INT NOT NULL PRIMARY KEY REFERENCES A (ida) ON DELETE CASCADE,
...)
WITHOUT OIDS;

Code: Select all

public class Key {
  public int IdA { get; set; }
  public int IdB { get; set; }
  public int Seq { get; set; }
}
...
using (AbcDataContext ctxt = new AbcDataContext())
{
  IEnumerable q =
    from a in ctxt.abcs
    where IdA = X && IdB == Y
    orderby Seq
    select new Key { IdA = a.IdA, IdB = a.IdB, IdC = a.IdC };

  foreach (Key k in q)
  {
     // This foreach goes over only 100 entities, even though the table
     // has 81715; in this case, if I remove the usage of the class Key,
     // and do select a (the Abc type), then the loop goes over the
     // correct set of entities.
  }
}