In SQL, which type of JOIN returns all rows from at least one of the tables mentioned from the FROM clause, providing those rows meet any WHERE or HAVING search conditions?

In SQL, which type of JOIN returns all rows from at least one of the tables mentioned from the FROM clause, providing those rows meet any WHERE or HAVING search conditions?

• Table Join
• Outer Join
• Comparison Join
• Inner Join 

 

EXPLANATION

Inner joins return rows only when there is at least one row from both tables that matches the join condition. Inner joins eliminate the rows that do not match with a row from the other table. Outer joins, however, return all rows from at least one of the tables or views mentioned in
the FROM clause, as long as those rows meet any WHERE or HAVING search conditions. All rows are retrieved from the left table referenced with a left outer join, and all rows from the right table referenced in a right outer join. All rows from both tables are returned in a full outer join.

SOURCE

https://technet.microsoft.com/en-us/library/ms187518(v=sql.105).aspx

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In Windows, if you want to format a hard drive or removable disk so it can be read and written by both Windows and Apple machines without using any 3rd party tools, you would format the disk as which of the following?

In Windows, if you want to format a hard drive or removable disk so it can be read and written by both Windows and Apple machines without using any 3rd party tools, you would format the disk as which of the following?

• HFS
• REFS
• exFAT
• NTFS 

 

EXPLANATION

Both Windows and Apple machines can read drives formatted in FAT32 and exFAT.  Apple can read NTFS but cannot write to it.

SOURCE

https://www.laptopmag.com/articles/format-drive-for-windows-and-mac

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Ext4 has the Max file size of ?

Ext4 has the Max file size of ?

• 16 TiB (for 16k block filesystem)
• 16 TiB (for 8k block filesystem)
• 16 TiB (for 4k block filesystem)
• 16 TiB (for 28k block filesystem) 

 

EXPLANATION

The ext4 filesystem can support volumes with sizes up to 1 exbibyte (EiB) and files with sizes up to 16 tebibytes (TiB).[12] However, Red Hat recommends using XFS instead of ext4 for volumes larger than 100 TB.[13][14]

SOURCE

https://en.wikipedia.org/wiki/Ext4

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Exchange Server 2016 is not supported on this server platform.

Exchange Server 2016 is not supported on this server platform.

• Windows Server 2012 x64
• Windows Server 2016 x64
• Windows Server 2016 Core
• Windows Server 2012 R2 x64 

 

EXPLANATION

We don't support the installation of Exchange 2016 on a computer that's running Windows Server Core or Nano Server. The Windows Server Desktop Experience feature needs to be installed. To install Exchange 2016, you need to do one of the following to install the Desktop Experience on Windows Server prior to starting Exchange 2016 Setup:
Windows Server 2012 and Windows Server 2012 R2: Run the following command in Windows PowerShell

Install-WindowsFeature Server-Gui-Mgmt-Infra, Server-Gui-Shell -Restart

Windows Server 2016: Install Windows Server 2016 and choose the Desktop Experience installation option. If a computer is running Windows Server 2016 Core mode and you want to install Exchange 2016 on it, you'll need to reinstall the operating system and choose the Desktop Experience installation option.

SOURCE

https://docs.microsoft.com/en-us/exchange/plan-and-deploy/system-requirements?view=exchserver-2016

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What is/was the purpose for using a Dynamic Disk Overlay?

What is/was the purpose for using a Dynamic Disk Overlay?

• Software to increase existing disk drives speed.
• Software to hide a disk drive from hackers.
• A dust cap for the disk drive to be used when cleaning the system.
• Software technique to extend a system BIOS that does not support logical block addressing (LBA). 

 

EXPLANATION

Dynamic drive overlay (DDO, also referred to as: software translation driver) is a software technique to extend a system BIOS that does not support logical block addressing (LBA) to access drives larger than 504 MiB. The technology was continued with similar types of problems up to the LBA-48 extension.

The most widespread vendor for such an extension is the company Ontrack which is licensing its DDO component to several of the major hard disk vendors for integration into their management tools and into their products.
The application of a Dynamic Drive Overlay (DDO), as licensed to Samsung Corporation for example, by Kroll Ontrack's version in their Disk Manager program is for the installation of various hard drives (Ultra/Super IDE/Parallel ATA) in computers that have older BIOS chips that do not recognize hard disk drives larger than 137.4 Gigabytes.[1] The interface is a software program that is loaded at start-up by the computer and augments the BIOS code, thus allowing the system to recognize and read areas of the hard disk drive that normally would not be accessible by the older BIOS.

This technique overrides some of the motherboard BIOS' hard disk controller driver in RAM. To allow access to the full size of any hard disk the software must be loaded before other programs try to access the upper parts of a disk with a critical size. To ensure that this extension gets loaded early most often the boot disk's master boot record is modified and the software installed at the beginning of the disk.

SOURCE

https://en.wikipedia.org/wiki/Dynamic_drive_overlay

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What settings in VMware would you use to keep VMs together or separate?

What settings in VMware would you use to keep VMs together or separate?

• Affinity rules
• NSX
• VDS
• Snapshots 

 

EXPLANATION

An affinity rule is a setting that establishes a relationship between two or more VMware virtual machines (VMs) and hosts.
Affinity rules and anti-affinity rules tell the vSphere hypervisor platform to keep virtual entities together or separated. The rules, which can be applied as either required or preferred, help reduce traffic across networks and keep the virtual workload balanced on available hosts.
If two virtual machines communicate frequently and should share a host, the VMware admin can create a VM-VM affinity rule to keep them together. Conversely, if two resource-hungry VMs would tax a host, an anti-affinity rule will keep those VMs from sharing a host.
Affinity rules and anti-affinity rules can be applied between VMs and hosts as well, and a VM can be subject to VM-VM affinity rules and VM-Host affinity rules at the same time. Affinity and anti-affinity rules in a vSphere environment can conflict with one another. For example, two VMs with an anti-affinity relationship may both be linked to a third VM via an affinity rule, but they cannot share a host. Optional affinity rule violation alarms can alert administrators to these events.

SOURCE

https://searchvmware.techtarget.com/definition/affinity-rules

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In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

Ctrl-Alt + keyboard keys corresponding to ASCII

Alt + ASCII decimal value on number pad

Shift-Alt + keyboard keys cooresponding to ASCII

Alt + ASCII decimal value using keyboard top 

 

EXPLANATION

I have used Alt + ASCI decimal value entered on the number pad for many years for various reasons.  It's a nice way to hide characters in passwords or files you want to keep secure. A password with an Alt-255 (null) character will display as a space and baffle even the most experienced hacker. While working in a public school system, my remote software client was VNC and it stored the password in hexidecimal format in the registry which above average students might
possibly be able to decode. But when ASCII 255 characters are found, they're totally confused. I have also named programs and batch files with just the null character plus extension to make it hidden.  I have also used ASCII extended box and line characters to make things look nicer in batch programs, but is limited with newer versions of Windows that lack ANSI.sys not being standard (it can be enabled).

SOURCE

https://support.office.com/en-us/article/insert-ascii-or-unicode-latin-based-symbols-and-characters-d13f58d3-7bcb-44a7-a4d5-972ee12e50e0

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