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These functions provide for the creation of, addition to, and retrieval
from tables within a Texis database. From the API the retrieval
mechanism does not use an index and will retrieve records sequentially
from the table. The order is undefined except from BTREE type tables
in which case the records will be returned in key order. Rewinddbtbl()
can be used to start reading from the beginning of the table again.
A BTREE type table is a special type of table in which the record data
is stored in a BTREE. The key is a composite key of all the fields
in the record. The keys are used in the same order of importance as
they were added to the data definition structure. While BTREE tables
offer some advantages for particular situations they also have some
limitations. Further indexes cannot be created on the table, and the
total record size for any record cannot exceed 8000 bytes.
When a table is created there must be a data definition structure
which describes the fields in the table. The structure can be created
with opendd(), and closed with closedd(). The data definition
structure is populated with calls to putdd(), which is documented in
the next section.
Copyright © Thunderstone Software Last updated: Sun Mar 17 21:14:49 EDT 2013
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