Commit b0c9b295 authored by Eric Coissac's avatar Eric Coissac

An OBIDMS is also contitued by views

parent 0b6c1f9f
......@@ -7,26 +7,27 @@ Formats
The OBItools3 Data Management System (OBIDMS)
*********************************************
An OBIDMS directory consists of :
An OBIDMS directory consists of :
* OBIDMS column files
* OBIDMS view descriptions
* an OBIDMS history file
OBIDMS column files
===================
Each OBIDMS column file contains :
* a header of a size equal to a multiple of PAGESIZE (PAGESIZE being equal to 4096 bytes
* a header of a size equal to a multiple of PAGESIZE (PAGESIZE being equal to 4096 bytes
on most systems) containing metadata
* one column of data of the same type
OBIDMS column files are read-only.
File name
---------
Each file is named with the attribute associated to the data it contains, and the number of
Each file is named with the attribute associated to the data it contains, and the number of
its version, separated by an underscore.
Example : ``count_0003``
......@@ -39,10 +40,10 @@ Header
------
The header of an OBIDMS column contains :
* Endian byte order
* PAGESIZE value / Size of the header
* Number of lines (total or without the header?)
* Data type (int, str...)
* Date of creation
......@@ -59,10 +60,10 @@ A column of data of the same type.
Versioning
----------
Since OBIDMS column files are read-only, any modification leads to the creation of a new version
Since OBIDMS column files are read-only, any modification leads to the creation of a new version
of the column file.
The first version of a column file is numbered 0001, and each new version increments that
The first version of a column file is numbered 0001, and each new version increments that
number by 1.
......@@ -72,19 +73,19 @@ Mandatory columns
Some columns must exist in an OBIDMS directory :
* sequence identifiers column
OBIDMS history file
===================
An OBIDMS history file consists of data that can be represented in the form of a directed acyclic
An OBIDMS history file consists of data that can be represented in the form of a directed acyclic
graph presenting the history of all the operations ever done in the OBIDMS directory.
OBIDMS views
============
An OBIDMS view corresponds to a list of OBIDMS columns and lines. A view includes one version
of each mandatory column. Only one version of each column is included. All the columns of
An OBIDMS view corresponds to a list of OBIDMS columns and lines. A view includes one version
of each mandatory column. Only one version of each column is included. All the columns of
one view contain the same number of lines in the same order.
......@@ -99,4 +100,3 @@ OBIIntColumn header file
========================
.. doxygenfile:: obiintcolumn.h
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