c-treeDB API API for C

Compatibility with other c-tree API Technologies

In This Section

Compatibility with FairCom DB ISAM and Low-Level Data Files

The basic requirement for FairCom DB ISAM and low-level data and index files to work with c-treeDB API is that the data file must have a DODA describing the fields and an IFIL describing the data and index structures. The DODA resource must have an entry for every field that forms a data record.

The c-treeDB API interface was designed to work best with ISEG structures with schema segments, that is, each index segment is a field declared in a DODA entry. c-treeDB API works with index segments defined in the ISEG structures using absolute record offsets and arbitrary lengths, that may or may not span more than one field in the record buffer, however, advanced features of c-treeDB API may not work as expected.

ctdbAlterTable(), ctdbSetRecordOn(), and ctdbFindRecord() are typical examples of functions that may not work as expected when dealing with absolute segment offsets.

Another source of problems may come from non-standard usage of c-tree field types declared in the DODA. There have been cases where CT_ARRAY fields being used as variable-length data, CT_STRING fields being used as fixed string fields. Another source of concern are CT_DATE, CT_TIME, and CT_DATETIME fields whose contents will not be compatible with the definitions of date and time used by c-treeDB API.

c-treeDB API was designed from the outset to be as compatible as possible with existing c-tree ISAM and low-level data. However, there are situations where c-treeDB API may not be able to handle very specific data type arrangements used by FairCom DB users in their custom applications.

Compatibility with FairCom DB SQL

Tables created with c-treeDB API are 100% compatible with FairCom DB SQL, even when tables are created without RECBYT or ROWID indexes. Tables created with c-treeDB API but without transaction processing flags will not be able to participate in SQL transactions or transaction isolation levels.

Tables created by FairCom DB applications must be 100% compatible with c-treeDB API to get the full benefit of all FairCom DB SQL commands and features. FairCom DB SQL makes extensive use of ctdbAlterTable(), ctdbFindRecord() and ctdbRecordSetOn(); any FairCom DB tables that do not support these operations will have reduced compatibility with FairCom DB SQL.

In This Section

Field mapping between FairCom DB SQL, c-treeDB API and c-treeDB API .NET

FairCom DB SQL Field Type	c-treeDB API/c-treeDB API .NET Field Type
BIT	CT_BOOL
TINYINT	CT_TINYINT
SMALLINT	CT_SMALLINT
INTEGER	CT_INTEGER
FLOAT	CT_FLOAT
DOUBLE	CT_DOUBLE
TID	CT_UINTEGER
CHAR	CT_CHARS
VARCHAR	CT_VARCHAR
LVARCHAR	CT_LVARCHAR
BINARY	CT_BINARY
VARBINARY	CT_VARBINARY
LVARBINARY	CT_LVARBIN
DATE	CT_DATE
TIME	CT_TIME
TIMESTAMP	CT_TIMESTAMP
BIGINT	CT_BIGINT
MONEY	CT_CURRENCY
NUMBER, NUMERIC, DECIMAL	CT_NUMBER