earthwork calculation

Tags: sum date have mem user span order by with rankBecause MySQL does not have a good support analysis function, now take the sum analysis function as an example, to do a MySQL calculation of the daily cumulative value MySQL Cumulative calculationSelectDateID Tran_dt, Regi_ch regi_ch, Tran_ch tran_ch, Ifnull (DRAW_CT,0) draw_ct, round (Ifnull (Draw_amt,0),2) Draw_amt, All_draw_ct, round (All_draw_amt,2) All_draw_amt from(SelectD.dateid, D.regi_ch reg

is obtained by sum ()Mysql> select SUM (age) from Stuinfo;Get averageMysql> Select AVG (age) from Stuinfo; All of these are group by ... that serve in groups ...Group calculation of total number of male and female studentsMysql> Select Sex,count (*) from stuinfo GROUP by sex;+------+----------+| sex | COUNT (*) |+------+----------+| Male | 3 || Women | 3 |+------+----------+ Having is used in conjunction with group by, and then adding group condition

1. Calculation of transmission time related to baud rate of bits per secondOne frame of data includes: 1 Starting Bits: 8 bits of data; 1 mark Bits; 1 Stop bits; Total 11bits; Existing three frames of data to be sent so there is 3*11bits sent; 1bits Transmit time = 1000/600 (Bit/ms) Time to send three frames = 3 * one * (1000/600) ms = 55MS; 2, about the baud rate 9600 bits per second involved in the transfer time

 calculation of MCS, modulation order, encoding rate, spectral efficiency relationship table Reference URL: http://4g-lte-world.blogspot.tw/2012/12/transport-block-size-code-rate-protocol.html Reference URL: http://blog.richliu.com/2013/10/22/1545/ (1) Premises: Therefore, the efficiency can be simplified to the following formula: tbs= size of the transfer block (table 7.1.7.2.1-1) crc= the number of bits that are attached for error checking =24

Tags: condition time () times Start sel from diff BirtMySQL age calculation (based on birthday field)Year (From_days (DateDiff (now (), birthdate))//Get Age now () current time, accurate to seconds DateDiff (begindate,enddate): Returns the number of days related to the date between two dates. From_days (days): Starting from 0000-00-00, returns a date based on the number of dates passed in; Year (date): Gets the years of the date[Condition Search age

PS: This blog post is written using Windows Live Writer 2012, and the format effect may not be good. In my development process, I encountered a statistical requirement, and the result was a request to return the number of days from the day that the definition input was calculated For this I have written a table-valued function to address this requirement. Now it is recorded and I hope to help some friends who have encountered such problems. First we look at the execution: Returns dat

A strange problem arises in the calculation of the date:If the current date is February 29 of a leap year, then for the current date + N years, then the corresponding date becomes February 28. But this does not accord with our common sense, according to common sense, when only 28 days, time should be postponed one day, become March 1.For example, the following SQL band is used to calculate this year's birthday date:SelectName,birthday,now (), Date_add

Label:ALTER FUNCTION [dbo]. [Getage] (@birthday DATETIME)RETURNS NVARCHAR (20)AsBEGINDECLARE @startDatetime DATETIMESET @startDatetime = @birthdayIF (@birthday is not NULLand ISDATE (@birthday) = 1)BEGINDECLARE @age NVARCHAR (20),@y INT,@m INT,@d INT,@now DATETIMESET @now = GETDATE ()SET @y = DATEDIFF (month, @birthday, GETDATE ())/12--set @m = DATEDIFF (month, @birthday, GETDATE ()) --Calculation monthSET @startDatetime = DATEADD (year,DATEDIFF (D, @

Label:days of difference between #两日期/time:to_days (end_time)-to_days (start_time)number of seconds between #两日期/time:SELECT Unix_timestamp (end_time)-Unix_timestamp (start_time);Time difference between #两日期/time score:SELECT sec_to_time (Unix_timestamp (end_time)-Unix_timestamp (start_time));The best way is to directly use the "+", "-" calculation, the current version is supported. For example: SELECT * FROM table_name WHERE Logindate Instance: Sele

usually means that the IO device is experiencing a bottleneck. As we all know, the process of sleep state does not need the CPU, even if all the CPU is idle, the process of sleep is not running, so the number of sleep process is definitely not suitable for measuring CPU load, Linux put uninterruptible The sleep process's calculation of load average directly overturns the original meaning of load average. So on the Linux system, the load average this

Real NumberAlso knownFloating Point Number. Floating PointThe decimal point is not fixed.Number of pointsThat is, the decimal point is fixed. IntegerIt can be seen asA special number of points, that is, the decimal point is at the end.. AverageFloating Point NumberA bit like scientific notation, including:Symbol bit,IndexAndThe ending part. In C #, there are three types of real-time variables: float, double, and decimal. Decimal has two important points:First, decimal is still a flo

wires and 12 multimode optical fiber cables for each cabinet at the beginning. However, more switches and server cabinets may be needed. Before installation, you can count the number of existing instances. If there are no ready-made devices or devices to be moved, a little foresight is required during installation. Consider the channels, switches, routers, servers, PBX or ip pbx systems, and any storage network or storage area network. KVM conversion and other monitoring also need to be connect

This article mainly introduces vue's simple real-time exchange rate calculation function, which has some reference value. Interested friends can refer to their own vue usage recently, compared with viewing tutorials and instances, it is better to write a demo by yourself. The small program has a simple but exquisite application with a simple exchange rate, and its expression is similar to that of vue, so I want to try it out by myself. 1. The first s

/document/query items A variety of programming jacks seem cumbersome and can be used without, so we can simplify the calculation of lucence formula Score (Q,D) = Coord (q,d) · ∑ (TF (T in D) IDF (T) 2) Conclusion TF-IDF algorithm is based on the term, the term is the smallest word breaker, which shows that the word segmentation algorithm is very important to the ranking based on statistics, if you use Chinese word segmentat

Js time interval calculation (number of days interval)Js time interval calculation (number of days interval) 1234567 function GetDateDiff(startDate,endDate) { var startTime = new Date(Date.parse(startDate.replace(/-/g, "/"))).getTime(); var endTime = new Date(Date.parse(endDate.replace(/-/g, "/"))).getTime(); var dates = Math.abs((startTime - endTime))/(1000*60*60*24); returndates; }

In the project often need to use the MD5 of the calculation file, for some purposes, MD5 calculation algorithm, usually in the network query, the general algorithm is to read the entire file stream of bytes, and then calculate the file md5, this way when the file is large, and there is a lot of concurrency, it can lead to memory explosion. So the following code provides several ways. And by calculating the

Python OpenCV histogram calculation and display method example, pythonopencv This article introduces how to use OpenCV Python to calculate histograms, and briefly introduces how to use NumPy and Matplotlib to calculate and draw histograms. The background knowledge and usage of the histogram are omitted. Here we will introduce the method directly. Calculate and display the Histogram Like in C ++, The OpenCV histogram

Significance and Calculation Method of Mysql database QPS and TPS The terms QPS and TPS are often mentioned in the monitoring of database performance. Next we will briefly share the meanings and calculation methods of QPS and TPS in the MySQL database. 1 TPS: the transaction volume per second. You can obtain the TPS value requested by the client application in the following way: Questions = show global s

Browsing this http://www.sitepoint.com station today, because of curiosity to read the code written by others, the results found this line of code,So I studied, calc () literally, we could interpret him as a function. In fact, Calc is the abbreviation for the English word Calculate (calculation), is a new function of CSS3, which is used to specify the length of the element. For example, you can use Calc () to set dynamic values for attributes such as

In the iOS app sandbox, documents and Library/preferences are backed up to icloud, so it's only appropriate to place some record files, such as plist, database files. Caches generally placed in the Library/caches,tmp folder are randomly cleared by the system and are not suitable for preventing data."Erase of picture cache"When using Sdwebimage, pictures are heavily cached and sometimes need to get the size of the cache and clear the cache.To get the cache size, use the GetSize method of the Sdim