Tables in this section contain data about data, but they are not support tables. These tables are broadly applicable to many different kinds of data, and thus do not belong in any other section.
This table lists and explains "behavior gaps": periods of time during which data (e.g. censuses, interactions, focal sampling) for an indicated group are (or are suspected to be) sparse, lacking, or simply lower than normal, for a known reason. The "known reason" is an important element of these gaps; periods of time where data collection happens to dip below the norm for unknown reasons are not included in this table.
Data from gap periods are not any less "valid" than data from any other times. However, when aggregating and analyzing data, the sparseness of data in a given period may affect the final results. The purpose of this table is to point out such periods and allow users to decide for themselves how to deal with them.
Reasons for gaps vary widely, so they are noted in a text column rather than with a support table of possible "gap reasons". This makes querying for reasons unwieldy, but this is by design; the table is intended to be used as a guide for thoughtful consideration[169] of time periods where gaps in observation may be affecting analyses.
When discussed in this table, a "gap" does not necessarily mean a complete absence of data for the indicated period. It may merely refer to periods where collected data is sparser than usual. Also, a gap does not necessarily indicate that all data types are uniformly sparse. It may be that the gap only applies to a single type of data. Users should pay attention to the Gap_End_Status and Notes columns for details about which data types are affected.
Identification of a gap is done by a data manager. The system is not involved with this process, and does not handle data from gap periods differently than data from any other time periods. Those kinds of judgments are left for the user to make.
A group may have overlapping behavior gaps; it's possible for more than one factor to affect observation of a group at the same time.
A gap's Gap_End must be
after its Gap_Start, or NULL.
The Gap_End can only be NULL
if the group's GROUPS.Cease_To_Exist is NULL. This allows for
recording of ongoing, not-yet-completed gaps.
A gap's Gap_End and Gap_End_Status must both be NULL or
both be non-NULL.
A unique integer identifying the BEHAVE_GAPS row.
This column is automatically maintained by the
database and must not be NULL.
The Gid of the group affected by this gap.
This column must contain a Gid value of a row on the GROUPS table. This column may not be NULL.
The date on which the gap began. This date must be between the group's GROUPS.Start and GROUPS.Cease_To_Exist, inclusive.
This column may not be NULL.
The date on which the gap ended. This date must be between the group's GROUPS. Start and GROUPS.Cease_To_Exist, inclusive.
This column may be NULL, see above.
The reason for, or status of, the gap's end. The legal values for this column are defined by the GAP_END_STATUSES support table.
This column may be NULL, see above.
Text notes about the gap, especially information about the gap's cause.
This column may not be empty, it must contain characters, and it must contain at least one non-whitespace character.
The timestamp range during which this row's data are considered valid. See The Sys_Period Column for more information.