Query_GrpSequentialsAndMissing
Explanatory Notes:

    This sample db demonstrates identification of data blocks as well as missing portions in a sequential series. Three types of source data are covered:

    (a) Number series.
    (b) Alpha-numeric series.
    (c) Date series.

    Subform on left shows all records, duly highlighting the start of each new block of sequential series. Subform at right depicts group-wise gist (for each PersonID) of sequential blocks as well as missing portions, duly indicating the start and end values for each set. Missing blocks are highlighted in light grey.

    Note:
    For identifying the start and end values for available as well as missing blocks in the given sequential series, an interesting technique has been used in this sample db, eliminating the need for any driver or temporary table. Instead, sliding comparison with projected next and previous values has been adopted through self joins based upon source data.

Version: Access 2000 file format.

References: Nothing extra.