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Real Time eXecutives,
Inc.
RTXHDB Historical Database
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RTXHDB is an extremely efficient database using
the 'flat file' model in which historical values are typically
stored time-sequentially in 4-byte floating-point format. RTXHDB
uses a separate file for each variable's historical data; the
name of the file is derived from the variable's index in an
'Index File'. Name lookup simply uses an Indexed Sequential
Access Method (ISAM); typical of any indexed database. The power
of the flat-file database comes from the fact that values are
stored in a time-sequential fashion so that access of a value at
a particular time requires a simple calculation of the value's
location in its data file. From that file position, a single read
retrieves time-sequential values. The result is extremely fast
access of large volumes of data. ( Unlimited Number of Tags )
FEATURES
- 65,535 tags per database, with as many databases as hard
disk space available
- Each
database has its own set of files with reduced databases
easily derived from other databases
- Database
can exist on one or more LAN file servers with transfers
up to 5,000 files per minute
- Data
buffering to provide protection against hardware and
software failures
- Many ways
to configure the data collection, buffering and storage
process
- Can
collect lab data, ASCII, Binary, etc.
- Tag name,
description, engineering units, high and low span values
available for every variable
- Multiple
formats: one, two, or four byte integer; four or eight
byte float available for storing data
- OPC-DA Client and
OPC-HDA Server Interface
Specifications
Requirements:
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Recommended:
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- Windows NT 4.0 / 2000 Server / XP Pro
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- Windows 2000 Server / XP Pro
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