Database Management Systems: Concepts, Security, and Design
Advantages of Distributed Databases
Distributed databases offer several benefits:
- Local Control of Data: Different departments or locations can manage their data locally.
- Increased Database Capacity: Distributing data across multiple servers increases overall storage capacity.
- System Availability: If one server fails, the database can often continue operating using other servers.
- Improved Performance: Queries can be processed faster by distributing the workload.
The DBA’s Role in Access Privileges
The
Read MoreOperating Systems Security and Resource Management
Virtual Memory
Why is it necessary to find contiguous main memory fragments for execution?
This is achieved through a combination of dynamic address translation and the use of page tables or segmentation. These mechanisms allow the operating system to divide a program’s memory space into smaller, manageable chunks that can be loaded into non-contiguous physical memory locations.
What is thrashing?
Thrashing occurs when the system spends excessive time swapping memory pages or segments between main memory
Read MoreEVO Application Development Notes
NOTE: I think we need to upgrade to MVC2 for the roles to work properly in EVO. Seems to me that when I tried this in MVC1 it dod not work.
- Users (Remember – everything in this application must be multi language)
- Add
- Should provide a notification (similar to table maintenance) when the user data is saved.
- After user is saved – the form needs to be reset.
- Create one user, then press create user again and you’ll see the “Username” entry box is disabled. This might be fixed if we reset to form after
Polar AW200 Activity Watch User Manual
Watch Buttons
SPAIN L
Clock Modes and Menu Structure
3. BEFORE THE ACTIVITY
Everyday Use
The Polar AW200 Activity Watch can be worn on the wrist at all times. Not only will it tell you the date and time, but also the ambient temperature and atmospheric pressure trend, and help you anticipate any change in the weather.
Measurement of Altitude
The measurement of altitude is based on a simple principle: the air pressure decreases as altitude increases.
For the altitude values to be accurate, it is necessary
Read MoreOperating Systems: Deadlock, Memory Management, and Virtual Memory
Deadlock
18-Spin-lock:
General (counting) semaphore using busy waiting instead of blocking. Used in multiproc OS to implement short critical sections.
19-Deadlock:
Two or more procs are waiting indefinitely for an event that can be caused by only one of the waiting procs.
20-Starvation:
Indefinite blocking. A process may never be removed from the semaphore queue in which it is suspended.
21-Monitors:
A high-level abstraction that provides a convenient and effective mechanism for process synchronization.
Read MoreUnderstanding Storage Technologies: SCSI, FC, iSCSI, and More
SCSI vs. FC
Interface for internal storage to external disks, used with SAN. Potential downtime with SCSI. RAID controller is SCSI hardware, while HBA is Fibre Channel hardware. Media specific (copper only), but it can be media independent—copper or fibre optic.
FC vs. iSCSI
Fibre Channel (FC): Current market leader for shared storage technologies. Provides the highest performance levels and is designed for mission-critical applications. The cost of components is relatively high, particularly per