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The main purpose of the database under the Info-Copernicus project is to provide information to three models, being developed within the project, on the basis of data collection on the selected households, as well as on the results of field operations, performed by co-executors.
The “Copernicus” Database consists of a number of functional blocks (separate functional block for each model), reflecting structure and content of studied domain, namely Block “Model of demand and supply balance for irrigation system”, Block “Model of field water-salt balance”, Block “Model of crop water consumption”.
The database was designed based on the following basic principles:
- openness – possibility to connect to the functioning databases of new blocks of information, tables and forms for processing them;
- providing information search and retrieval according to a group of parameters (features);
- providing capability to re-organize and expand when changes in domain limits occur;
- providing simplicity and ease of information input and updating as well as of user referring to relevant information (on the basis of user interface);
- providing possibility of shared user access to information;
- availability of developed user interface, allowing to efficiently link all components of database (blocks, tables, forms and so on) into a single integral system, and organize performing the duties given to database;
- all data domain is presented as objects, which are elements of domain information that have certain properties;
- all objects have certain properties (characteristics), i.e. information of various types, through which the object is presented in database;
- the main studied objects are encoded by using the method of compound coding, and additional ones – using the method of level-by-level coding as a particular case of compound coding. Selection of these methods is based on that they allow not only to uniquely determine objects on a set of domain objects, but also to reflect their hierarchy and sequence order.
In the process of analyzing domain, various objects being studied were identified. For individually and uniquely determining them among all set of studied domain objects, it is necessary to give them appropriate codes. Coding used in this system meets definite requirements, namely:
- univocacy - only one code is given to each object, and only one object corresponds to each code;
- possibility to expand and include - a set of coded objects can increase. Thus, it is necessary that a set of codes and coding function let give codes to new objects;
- conciseness - object is usually encoded in order to avoid the need to denote it by a name long and difficult in use. Therefore, the codes should be short, but at the same time the length of code should be defined in view of requirements for expanding and including;
- mnemonic presentation - i.e. the applied codes should characterize the denoted objects from meaningful side.
Three ways are used as coding procedures in the database, namely:
- serial coding - according to this procedure, the objects, belonging to some set of objects, are given sequential numbers;
- compound coding - object codes consist of several zones, called descriptors, each of which has a concrete informative significance;
- level-by-level coding - this coding procedure is based on setting codes, consisting of several zones (levels), at that each of these zones presents some set of objects. These zones, viewed from left to right, usually present more and more limited sets of objects.
For maximum information linkage with regard to corresponding information objects, the system of object coding, used in the given database, takes into account the coding system, put in the WARMIS.
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