Tutorial by Examples: c

CREATE INDEX ix_cars_employee_id ON Cars (EmployeeId); This will create an index for the column EmployeeId in the table Cars. This index will improve the speed of queries asking the server to sort or select by values in EmployeeId, such as the following: SELECT * FROM Cars WHERE EmployeeId = 1 ...

Both the math and cmath-module contain the Euler number: e and using it with the builtin pow()-function or **-operator works mostly like math.exp(): import math math.e ** 2 # 7.3890560989306495 math.exp(2) # 7.38905609893065 import cmath cmath.e ** 2 # 7.3890560989306495 cmath.exp(2) # (...

The math module contains the expm1()-function that can compute the expression math.e ** x - 1 for very small x with higher precision than math.exp(x) or cmath.exp(x) would allow: import math print(math.e ** 1e-3 - 1) # 0.0010005001667083846 print(math.exp(1e-3) - 1) # 0.0010005001667083846 p...

Supposing you have a class that stores purely integer values: class Integer(object): def __init__(self, value): self.value = int(value) # Cast to an integer def __repr__(self): return '{cls}({val})'.format(cls=self.__class__.__name__, ...

A basic Employees table, containing an ID, and the employee's first and last name along with their phone number can be created using CREATE TABLE Employees( Id int identity(1,1) primary key not null, FName varchar(20) not null, LName varchar(20) not null, PhoneNumber varchar(10)...

Click the Run button in the toolbar (or press ⌘R) to build & run your project. Click Stop (or press ⌘.) to stop execution.   Click & hold to see the other actions, Test (⌘U), Profile (⌘I), and Analyze (⇧⌘B). Hold down modifier keys ⌥ option, ⇧ shift, and ⌃ control for more variants.  ...

You can have multiple versions of Xcode installed at the same time (including beta versions). Simply rename the application in Finder to avoid conflicts. Note: Installing Xcode from the App Store will tend to overwrite an existing version on your machine. You can also install Xcode from a direct ...

CREATE TABLE HR_EMPLOYEES ( PersonID int, LastName VARCHAR(30), FirstName VARCHAR(30), Position VARCHAR(30) ); CREATE TABLE FINANCE_EMPLOYEES ( PersonID INT, LastName VARCHAR(30), FirstName VARCHAR(30), Position VARCHAR(30) ); Let's say we want to ...

You can list existing git aliases using --get-regexp: $ git config --get-regexp '^alias\.' Searching aliases To search aliases, add the following to your .gitconfig under [alias]: aliases = !git config --list | grep ^alias\\. | cut -c 7- | grep -Ei --color \"$1\" "#" The...

All built-in collections in Python implement a way to check element membership using in. List alist = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] 5 in alist # True 10 in alist # False Tuple atuple = ('0', '1', '2', '3', '4') 4 in atuple # False '4' in atuple # True String astring = 'i am a s...

dict have no builtin method for searching a value or key because dictionaries are unordered. You can create a function that gets the key (or keys) for a specified value: def getKeysForValue(dictionary, value): foundkeys = [] for keys in dictionary: if dictionary[key] == value: ...

Sorted sequences allow the use of faster searching algorithms: bisect.bisect_left()1: import bisect def index_sorted(sorted_seq, value): """Locate the leftmost value exactly equal to x or raise a ValueError""" i = bisect.bisect_left(sorted_seq, value) ...

Searching in nested sequences like a list of tuple requires an approach like searching the keys for values in dict but needs customized functions. The index of the outermost sequence if the value was found in the sequence: def outer_index(nested_sequence, value): return next(index for index, ...

If the query column names do not match your classes you can setup mappings for types. This example demonstrates mapping using System.Data.Linq.Mapping.ColumnAttributeas well as a custom mapping. The mappings only need to be setup once per type so set them on application startup or somewhere else ...

To check the equality of Date values: var date1 = new Date(); var date2 = new Date(date1.valueOf() + 10); console.log(date1.valueOf() === date2.valueOf()); Sample output: false Note that you must use valueOf() or getTime() to compare the values of Date objects because the equality operato...

Using the Cars Table, we will calculate the total, max, min and average amount of money each costumer spent and haw many times (COUNT) she brought a car for repairing. Id CustomerId MechanicId Model Status Total Cost SELECT CustomerId, SUM(TotalCost) OVER(PARTITION BY Cust...

Using the Item Sales Table, we will try to find out how the sales of our items are increasing through dates. To do so we will calculate the Cumulative Sum of total sales per Item order by the sale date. SELECT item_id, sale_Date SUM(quantity * price) OVER(PARTITION BY item_id ORDER BY sale...

When the Repeater is Bound, for each item in the data, a new table row will be added. <asp:Repeater ID="repeaterID" runat="server" OnItemDataBound="repeaterID_ItemDataBound"> <HeaderTemplate> <table> <thead> ...

Rebasing reapplies a series of commits on top of another commit. To rebase a branch, checkout the branch and then rebase it on top of another branch. git checkout topic git rebase master # rebase current branch onto master branch This would cause: A---B---C topic / D---E---F---G...

ALTER TABLE Employees ADD StartingDate date NOT NULL DEFAULT GetDate(), DateOfBirth date NULL The above statement would add columns named StartingDate which cannot be NULL with default value as current date and DateOfBirth which can be NULL in Employees table.