Metadata Features
Each metadata feature describes the contents of one of the following records from the CCOGIF file:
Record Name |
Description |
VDR |
Volume Descriptor Record: contains information about the entire CCOGIF volume, such as its creation date and generating agency. |
UFLR |
User Fixed Length Record: contains any user data associated with the CCOGIF volume or dataset. It simply contains free-form ASCII data. |
DSHR |
Data Set Header Record: describes each dataset contained in a CCOGIF volume. It contains some extraneous information about the data (name, creation date, geographic location, etc.), as well as information pertaining to the interpretation of the data itself (X, Y, and Z data types, topology information, map projection information, etc.). |
EMDR |
Entity Metadata Record: describes the source and quality of the entity data contained in a dataset. There are one or more of these records following each DSHR record. |
DGHR |
Data Group Header Record: is the first record of each data group within a CCOGIF dataset. It provides a name for the group, as well as provides counts of how many point, line, and area themes are contained in the group. |
DTHR |
Data Theme Header Record: describes the contents of a single data theme. It provides information about the entity data itself (entity type, number of entities), as well as a count of user attributes defined on each entity and a calculation of the length of the fixed-length part of each entity in the theme. |
ADR |
Attribute Descriptor Record: There is one attribute descriptor record in each data theme. It is a variable-length record that describes the names and types of attributes defined on each entity contained in the theme. |
EOVR |
End Of Volume Record: marks the logical and physical end of the CCOGIF volume. It is always the last record in a CCOGIF file. |
All metadata features have a feature type of CCOGIF_METADATA. The CCOGIF record described by a metadata feature is reflected by the value of the attribute ccogif_record_code. This attribute has one of three or four character record names listed in the above table.
Each metadata feature has a particular set of attributes, depending on the CCOGIF record it represents. The following sections list the attributes for each record type.