Client-server operation mode is used in workgroups or on enterprise scale. It is implemented as a three-tier architechture:
1C:Enterprise Client
1C:Enterprise Server Cluster
Database server
An important feature of 1C:Enterprise 8 interaction with database is that
there are no specifics for user or application developer, which would depend on
which operation mode will be used with an applied solution. It is unique that 1C:Enterprise 8 framework takes up all issues of interaction with a
database, whichever it would be. Developers, let alone users, do not have to
think about the database issues.
A client application interacts with a cluster server, and the cluster accesses the database server, if necessary.
At that 1C:Enterprise server cluster can operate on one same computer, or on different ones. This feature allows system administrators to distribute workload across several servers, if it is necessary.
Using a server cluster allows to set to the most complicated data processing operations to be done by the cluster. Then the client application will get only result of the processing, whatever difficult it would be. Usually, it is much easier to upgrade a server cluster, than the whole stock of client computers.
Deploying of a server cluster and its technical administering is quite simple. For example, creation of a database is done during launching of the Designer (same as for file operation mode).
Supported Database Types
MS SQL
1C:Enterprise 8 uses MS SQL Server features for efficient information
retrieval from a database:
Query mechanism is designed for maximal use of MS SQL Server to perform
calculations and report preparation.
Browsing of long dynamic lists is provided without many database calls.
At that, users are provided the functionality of efficient data search,
filtration and sorting.
PostgreSQL DBMS
When running in client-server mode 1C: Enterprise 8.1 (and later) supports
operation with PostgreSQL DBMS.
PostgreSQL is an open-source DBMS and 1C:Enterprise 8.1 (and later) uses a
modified version of PostgreSQL. PostgreSQL installation package for
1C:Enterprise is included into the 1C:Enterprise 8 distribution kit. The
installation package contains versions for MS Windows and Linux operating
systems.
1C:Enterprise 8 has some features in operation with PostgreSQL, concerning
using of transactional locks:
In automatic lock control in transactions mode database table locks are
used.
In managed locks in transactions mode database field and record locks
are used.
IBM DB2®
IBM DB2 is another database management system supported by the platform. There are no specifics in operation of 1C:Enterprise 8 with
IBM DB2 database.
Oracle
Oracle® database is used in the same way as other DBMS. The
illustration below shows the place of a DBMS in client-server architecture
with 1C:Enterprise 8 server cluster.
This mode is intended for personal use, or small number of workplaces in a
LAN (up to 5 or so).
In this mode all information base data (configuration, database and service
information) is located in a single file.
There is no need in additional software tools to work with the information
base – it is enough to have OS and 1C:Enterprise 8.
File mode provides high integrity of information base and simple way to
create backup copies (by means of simple copying of the information base file to
some backup location).
The transaction mechanism provided by the platform minimizes the risk of data lost or corruption in cases like PC or network power failure. But of course, using client-server operation mode gives better reliability since data on the server side are independent and safe from possible failures on client computers.
The platform distribution kit includes a software utility for testing and repairing of file database after failures.
Operation with File Database Using Thin and Thick Clients
When thick client is used, the client itself implements all functionality of the file database.
If thin client is used, then a special server environment is established on the PC where the client is running, including -
loading server components required for system operation,
loading the configuration,
other actions necessary for normal system operation with the information base.
From point of view of thin client, the established environment acts as a server. From point of view of the operating system the environment is not a separate process and is executed within the thin client process.
Operation with File Database over a Web-Server
It is possible to operate with file database over a Web-server using thin client or Web-client.
In this case, the Web-server extension module creates a similar server environment on the Web-server, for each information base. The component for file database operation and information base data are loaded right into the web-server address space. At that the Web-server load increases significantly; users of one information base cannot operate in parallel - all their queries are put into one queue.
Therefore, this operation mode is more for testing purposes, or for very limited workgroups in some special cases.
Client-server Mode
This mode is implemented on the basis of three-tier client-server
architecture (see picture).
The client-side software interacts with 1C:Enterprise 8 server cluster, and the cluster, if necessary, interacts with a database
server (one of the supported database servers). At that,
physically, a server cluster and database server may be located on one PC, as
well as on different computers. This allows an administrator to distribute
workload between servers, if necessary.
Using 1C:Enterprise 8 server cluster allows to concentrate most complex data
operations on it. For example, execution of complex queries is performed on
server side, while client software receives only required data selection.
Usually, performance of server cluster is simpler to upgrade, than to upgrade a
whole workgroup hardware (clients).
Another important point of this architecture is structured user access to an
information base and it is more efficient to administer it. All user access goes
through 1C:Enterprise 8 server cluster. To access a database, user only needs to
specify the cluster name and the information base name required. The system then
asks for user name and password.
It is also easy to install a server cluster. For example, an information base
is created using the Designer tool
(just the same as for the file mode). The 1C:Enterprise 8 distribution kit
includes the client-server administration utility that gives means to manage
information bases and user access.
