what is cname record

In a single statistic, I used the group in MongoDB to summarize a record number 100W table. The result is an unexpected message. Error in executing GroupByCommand ' group ' failed:exception:group () can ' t handle more than 20000 unique keys (response: {"errmsg": "Exception:gr OUP () can ' t handle more than 20000 unique keys "," code ": 10043," OK ": 0.0})Type:MongoDB.Driver.MongoCommandException From the

the data on the hard disk as a file presented to the user. FAT32, NTFS are common file system types.Second, you can develop applications that run directly under UEFI, which usually ends with EFI. Since UEFI can directly identify files in a FAT partition, there are applications that can be run directly in it. Then you can completely make the Windows Installer into an EFI-type application, and then put it in any FAT partition to run directly, so that the installation of the Windows operating syst

From: http://www.360doc.com/content/11/0628/21/1330004_130212218.shtml On many download points, in addition to the format of the table after the video, it will also be marked as tvrip, ts, etc. What do these mean? Through the following content, you can simply understand them. 1. Cam (GUN) Edition Cam uses digital cameras to steal videos from cinemas ". Because the camera is often jitters during the video p

Bandwidth, transmission speed, two bytes, killing people, always confused which is bit, which is byte, the network speed is 10 m, M indicates bit or byte Article Article Record that Mbps is actually a bandwidth unit, not a speed unit. In Mbps, "B" refers to "bit )". The act

Label:When creating a new index, or rebuilding an existing index, you can specify a fill factor, which is the number of data pages in the index that are populated when the index is created. A fill factor of 100 means that each index page 100% fills up, and 50% means that each index page 50% fills up. If you create a clustered index with a fill factor of 100 (on a non-monotonically incrementing column), it m

First of all, I admit I saw what other people did.Because I have no experience, although I know that Echo is caused by the x-forwarded-for parameter, but it has not been available so I looked at the demo.Because it involves writing a script to record the injection process, I hereby recordI saw 2 demos. The most straightforward one

This article is absolutely original, welcome to reprint, but reprint please remember to indicate the origin of the article: http://blog.csdn.net/izard999/article/details/39891281 have been working on Android for nearly 4 years, recently changed to a unit to do technical director, get outsourced code found is Struts2 do, 5 years ago on the Struts2 or have some insights, but because years do not, leading to

thatDatabase recovery will take place after the system crashes.Transactions that are used to restore and revoke a system crash in an active stateThe impact on the database,Thus guaranteeing the atomicity of the transaction.The system changes any actual data on the disk beforeThe information that modifies the operation information itself is logged to disk.When a crash occurs,The system was able to record th

Most of the time, I use the SSH command line to connect to my remote server. Unfortunately, my SSH session is lost because the power is down today and the network hub is closed. What if your SSH session for an important job is lost? Here

Jump into the first pitfall in linux-disk recovery due to installation of Ubuntu is mistakenly restored. (record of TestDisk usage), ubuntutestdisk Skip to operation instructions if you don't talk nonsense. Just a few days ago, I was eager to replace my old laptop with a Linux operating system, and it was just a step into Linux in my spare time. Just do it, select Ubuntu for the release, and downloadUbuntu1

41778.00000000 41778.77877315 What kind of a time record is this? In writing a small program, referring to another software data frame, the software with "41778.77877315" this form to record time, do not understand, do not know how to convert, not the Unix time stamp, which hero pointing, thank you Reply to disc

How to use%type and%rowtype in Oracle PL/SQL1. Using%typeIn many cases, a PL/SQL variable can be used to store data in a database table. In this case, the variable should have the same type as the table column. For example, the first_name column of the students table is of type VARCHAR2 (20), and we can declare a variable as follows:DECLAREV_firstname VARCHAR2 (20);But what happens if the definition of the

Turn: SourceHttp://www.ruanyifeng.com/blog/2015/09/0x7c00.htmlThe computer principles textbook says that the master boot record is stored in memory address 0x7c00 at startup. This strange address, how to come, the textbook will not explain. I have always wondered, why not put in the memory of the head, tail, or other location, and just deposit this 1024 bytes smaller than 32KB place? Yesterday, I read an ar

Symmetric tree Given a binary tree, check whether it is a mirror of itself (ie, shortric around its center ). For example, this binary tree is unsupported Ric: 1 / \ 2 2 / \ / \ 3 4 4 3 But the following is not: 1 / \ 2 2 \ \ 3 3 Note:Bonus points if you cocould solve it both recursively and iteratively. Confused wha