Login:
  • Home
  • →
  • Desktops
  • →
  • Free manual HP   HP NonStop G-Series
Votes - 0, Average rating: 0 ( )

User manual HP, model HP NonStop G-Series

Manafacture: HP
File size: 221.61 kb
File name:
Language of manual:enesfr
Free link for this manual available at the bottom of the page



Other manuals for this model:

manual abstract


Introduction
ENFORM Processing Environment
The Query Compiler/Report
The query compiler/report writer has two functions or phases: (1) compiling the
Writer
query and (2) formatting and writing a report.
During the first phase, the query compiler checks the query specifications for
syntactical correctness. If the query compiler detects errors at this time, query
processing is stopped and a syntax error message is issued.
If the query specifications are correct, the query compiler compiles the query
specifications into a form (called a compiled representation of the query) that can be
understood by the query processor. The compiled representation of the query
includes information from the dictionary about the records and fields from which data
is to be retrieved. It also contains information about qualifications in the query
specifications that limit the number of records read from the data base and written to
the target records (the temporary records built by the query processor from which
your ENFORM output is produced). The query compiler sends the compiled query
representation to the query processor in an interprocess message.
During the first (or compilation) phase, the query compiler also builds an internal
report specification that is used by the report writer during the second (or report-
writing) phase.
The second phase occurs only if the query specifications contain a request for a report
(the presence of a LIST statement within the query specifications requests a report).
During this phase, the report writer reads each target record returned by the query
processor, formats it using information from the internal report specification built
during the first phase, and produces the report.
The Query Processor
The query processor is a server process that receives query specifications and record
description information from the query compiler. After receiving this information, the
query processor retrieves data from the data base. The query processor exists in one of
the following forms:
1.
As a dedicated server process that is created for and provides services to an
individual query compiler/report writer process. This dedicated server process is
created each time an ENFORM session is initiated. One dedicated query processor
executes all the ENFORM queries within the session.
2.
As a named server process that can be shared (sequentially) by several ENFORM
queries. This type of process exists until it stops or times out, has a backup
process, and handles queries one at a time.
The query processor automatically chooses a strategy for accessing your data base by
using information from the dictionary and the file system. It uses its own search
algorithms to reduce the number of data base accesses needed to produce the specified
data. The query processor produces target records containing all the data requested in
the query specifications. The query processor places the target records in a temporary
work file called a target file.
058058 Tandem Computers Incorporated
1–5

...

Other models in this manual:
Desktops - HP NonStop L-Series (221.61 kb)

Reviews



Your review
Your name:
Please, enter two numbers from picture:
capcha





Category