Accessing the database

The user queries the database in two steps. These are repeated until a satisfactory result has been achieved. They include  

Step 1 searches in the database to identify the subset of accidents and near accidents that meet certain search criteria and Step 2 presentations of the results in the form of event descriptions, statistical summaries etc. 

Administrative conditions Date, time Department (free-text description or fixed alternatives) Place (free-text description) Registration number (added by the system) Person to contact for more details about the event 

Injured persons Information about injured persons (name, age, occupation)  

Work situation Activity (free-text description) System/equipment involved (free-text description, eventually tag number)  

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Access to CAS databases is only possible on computers on which the SciFinder software has been installed. Tt is directly available at CAS, computational seiwice centers, or library seiwices with online access. The database is not free of charge access can be obtained only via these services. After the licensed software has been installed and online access is obtained, the program tan be started. 

The Research Institute on Fragrance Materials maintains the most comprehensive worldwide source database on fragrance/flavour components including acute aquatic toxicity, biodegradation data, human health issues, for example, carcinogenesis, sensitization. A password is required to access the database. 

Data access services, a layer that centralizes services to access the databases... 

BioPrint consists of a large database and a set of tools with which both the data and the models generated from the data can be accessed. The database contains structural information, in vivo and in vitro data on most of the marketed pharmaceuticals and a variety of other reference compounds. The in vitro data generated consist of panels of pharmacology and early ADME assays. The in vivo data consist of ADR data extracted from drug labels, mechanisms of action, associated therapeutic areas, pharmacokinetic (PK) data and route of administration data. 

Many libraries provide dial-in, Internet, or telnet access to their periodical databases as an option in their catalog menu. However, licensing restrictions usually mean that only researchers who have a library card for that particular library can access the database (by typing in their name and card number). Check with local public or school libraries to see which databases are available. 

Activeparts is a web site that contains a database of over 1,000,000 parts. Oread Capture CIS can link to this site and download part information to your schematic. This information can include vendor information, a graphic symbol for the part, and a footprint for PC board layout. To access the database with the schematic displayed, type z to place a database part ... 

The different functions are separated because they have different requirements for accessing the database, for interacting with the external world, for performance and for localization. These requirements are summarized in Table 1. 

Metadata—"Data About Data" In a database, metadata describes the structure, format, storage, access, and various properties of other stored data, or it describes the characteristics of the database itself Metadata is sometimes stored in tables termed "dictionaries." As an example, chemical metadata might include the tablename, fieldname, and format of the field containing the chemical structures. This metadata might be stored in a master table in the database and be stored as proper-ty name and property-value pairs, which the application that accesses the database can understand. 

The computer based identification of crystalline phases in powder diffraction patterns normally requires two separate components (a) a powder diffraction database containing reference information and (b) a search-match program that loads the diffractogram and accesses the database to attempt to match the diffraction data to known phases in the database. 

The API interfaces to SRS provide an object oriented programmers interface into an SRS system. This allows programmers to access the databases in their SRS system from their programs written in C++, Perl, Java or Python. The databases can be queried and information retrieved about the set of entries. The SRS system itself can be interrogated about the databases available and the fields which can be queried within those databases. 

A table in a relational database is intended to provide a consistent way to organize large amounts of data, constrain the data in meaningful ways, and extend the tables when new data becomes available. It does not contain any formatting or display information. Programs that access the database provide any display or formatting of the data in the table. 

The large amoimt of complex and coupled information, their proper presentation and statistical evaluation will require new approaches in data management. The extraction and visualisation of specific data will be problematic, especially when a lot of different users access the database via internet to add and extract data. The advantage of such a system is, that it is growing and learning from different work groups all over the world. 

Reduction of network traffic Concentrating the function of accessing database and other systems on the application server makes it possible to reduce network traffic between the client and the server. That is, instead of interacting with the database directly, the client calls the business logic on the application server, and then the business logic accesses the database on the database server on behalf of the client. Therefore, only service requests and responses are sent between the client and the server. From the viewpoint of network traffic, comparisons of two-tier architecture and three-tier architecture are shown in Figure 7. 

Concurrency control Mechanisms that ensure that each individual accessing the database can interact with the database as if they were the only user of the database, with guarantees as to the behavior of the system when many users seek to read from or write to the same data item at the same time. 

The most efficient way to access FlyBase, BDGP, and EDGP is via the WWW, which requires a computer, a connection to the Internet, and browser software, such as Netscape or Internet Explorer. The addresses (or uniform resource locators, URLs) on the Web to access the databases are shown in Table 28.1. 

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