A method of data loading for large information warehouses includes performing checkpointing concurrently with data loading into an information warehouse, the checkpointing ensuring consistency among multiple tables; and recovering from a failure in the data loading using the checkpointing. A method is also disclosed for performing versioning concurrently with data loading into an information warehouse. The versioning method enables processing undo and redo operations of the data loading between a later version and a previous version. Data load failure recovery is performed without starting a data load from the beginning but rather from a latest checkpoint for data loading at an information warehouse level using a checkpoint process characterized by a state transition diagram having a multiplicity of states; and tracking state transitions among the states using a system state table.