Tags: Numeric functions: 1, rounding function round () from dual: A row of a column composed of select round (23.4) from dual;--default not write m means m 0 select round (23.45,1) from dual;--1 After leaving a decimal point, then the second digit of the decimal point rounding Select Round (23.45,-1) from dual;---1 means rounding the rounding before the decimal point, the previous one is 3 rounded to 20 2, the Rounding function: Select Ceil (23.45),
Keywords: Oracle numeric function-type date conversion To_char automatic type conversion Date type numeric converter other function numeric functionABS: Find the absolute value function, such as: ABS (−5) 5SQRT: square root function, such as: sqrt (2) 1.41421356Power: exponentiation function, such as: 2,3 8COS: cosine trigonometric functions, such as: cos (3.14159) −1MoD: Find division remainder, such as mod (1600, 300) 100Ceil: The smallest integer g
()-- Dateadd (date part, value to be added, date): add the corresponding value according to the specified date part.Select dateadd (mm, 2, '2014/1/1') -- display 2013/2Select dateadd (YY,-2, '2014/1 ') -- display 2013/2-- Datediff (date part, date 1, date 2): Calculate the gap between two dates based on the date part (I .e., date 2-date 1)Select datediff (mm, '2014/1/1', '2014/3/5') -- display 5Select datediff (mm, '2014/1/5', '2014/3/1') -- show-5-- Datename (date part, date): obtains the stri
, and the last read of the string is read into the line feed. Therefore, when you call the Fgets function, you can read a maximum of n-1 characters. At the end of the read, the system will automatically add ' + ' at the end and return with STR as the function value.2.2 fputs functionThe Fputs function is used to output a string to a file. The Fputs function is called in the following form:Fputs (str, FP);Here, the FP is the file pointer; Str is the string to be output, which can be a string cons
Single-record functions in SQL1. ASCIIReturns the decimal number corresponding to the specified character;SQL> select ascii ('A') A, ascii ('A') A, ascii ('0') zero, ascii ('') space from dual;A ZERO SPACE------------------------------------65 97 48 322. CHRReturns the corresponding characters;SQL> select chr (54740) zhao, chr (65) chr65 from dual;ZH C---Zhao3. CONCATConnect two strings;SQL> select concat ('010-', '000000') |' to 23' Gao Qian competin
SQL has many built-in functions that can be used for counting and computation.Syntax of the functionThe syntax for the built-in SQL function is:SELECT function (column) from tableTypes of functionsIn SQL, there are several kinds of basic function types and types. The basic types of functions are:
Aggregate function
Scalar function
aggregate function (Aggregate
# Each loop creates a new function and then returns the 3 functions that were created def F (): return i*i fs.append (f) Return FS# call >>> f1,f2,f3=>>> F1 ()9>>> f2 ()9>> > f3 ()9Why is it all 9?!The reason is that the returned function refers to the variable I, but it is not executed immediately. When all three functions return, they refer to the variable i has become 3, s
to 0)1 Sample:2 Select round(123.456,0) fromDual Return123
3 Select round(123.456,1) fromDual Return123.5
4 Select round(-123.456,2) fromDual Return-123.46 3.ceil and Floor functionsThe ceil and floor functions are sometimes useful when it comes to business data. Ceil (n) takes the smallest integer greater than or equal to the value N, and Floor (N) takes the largest integer less than or equal to the value N; turn from: http://www.2cto.com/database/2
Oracle date functions:
Months_between: returns the difference of the month between two dates months_between ('01-EP-95 ', '11-Jan-94') ==> 19.6774194 add_months: Number of copies added to the date. add_months ('11-Jan-94 ', 6) ==> '11-JUL-94' next_day: Specifies the day after the date. next_day ('01-SEP-95 ', 'Friday') ==> '08-SEP-95' last_day: the last day of the month. last_day ('01-SEP-95) ==> '30-SEP-95 'Round: Rounding date round ('25-JUL-95', '
Oracle date functions/character functions/numeric functions/conversion functions/Aggregate functions Oracle date functions: [SQL] MONTHS_BETWEEN: returns the difference of the month between two dates MONTHS_BETWEEN ('01-EP-95 ', '
, Job)# * Number preceded by the required parameter, followed by the named keyword parameter# If there is already a mutable parameter in the function definition, then the named keyword argument will no longer need a delimiter. def person (name,age,*args,city,job): print(name,age,args,city,job)# A named keyword function can have a default value def person (name,age,*,city='Beijing', job='student' ): print(name,age,city,job)fromimport person >>> person ('jiaxinwei',Beijing studentIt's not
Single record function in SQL 1. ASCII returns the decimal number corresponding to the specified character; SQLselectascii (A) A, ascii (a) a, ascii (0) zero, ascii () spacefromdual; The AAZEROSPACE------------------------------------659748322.CHR gives the integer, returns the corresponding character; SQLselect
Single record function in SQL 1. ASCII returns the decimal number corresponding to the specified character. SQL select ascii (A) A, ascii (a) a, ascii (0) zero, ascii () space from dual;
This article is not ready to introduce all of the Oracle functions, in the current situation, I do not have this time, need to learn too much, to spend most of the time on learning to use the technical aspects:), so if you are ready to learn all the Oracle functions of friends, or to focus on: Oracle SQL Reference official documents are more reliable.
This article will cover a number of
Why a constructor cannot be a virtual functionC++
From the storage space point of view, the virtual function corresponds to avtableA pointer to a virtual function table, which we all know, but this pointvtableThe pointer is actually stored in the object's memory space. The problem is that if the constructor is virtual, you need to passvtableTo invoke, but the object is not instantiated, that is, the memory space is not yet, how to findvtableIt? So the constructor cannot be a virtual f
function is a kind of encapsulation supported by Python, we can decompose complex tasks into simple tasks by splitting large pieces of code into functions through a layer of function calls, which can be called process-oriented programming. function is the basic unit of process-oriented program design.Incoming functionThe function itself can also be used as a parameter. Python's built-in MapReduce function. (from Google, then Doug this guy was open sou
Common functions that cannot be declared as virtual functions are: ordinary function (non-member function), static member function, inline member function, constructor, friend function.1. Why does C + + not support ordinary functions as virtual functions?The normal function (non-member function) can only be overload, c
Common functions that cannot be declared as virtual functions are: ordinary function (non-member function), static member function, inline member function, constructor, friend function.1. Why does C + + not support ordinary functions as virtual functions?The normal function (non-member function) can only be overload, c
Common php functions: user-defined functions, callback functions, recursive functions, etc.
Common php functions, examples of php user-defined functions, callback functions, va
JavaScript ------ functions (general functions, dynamic functions, anonymous functions)
Function
I. general functions
1. format:
Function Name (formal parameter ...)
{
Execute the statement;
Return value;
}
A function is the encapsulation body of multiple execution statement
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.