Databases Midterm
What is an update anomaly
When one or more instances of duplicated data is updated
In PHP can identifiers have the same name as a function?
Yes
How to bulk insert into SQL
INSERT INTO Table1 VALUES (1, 'FirstName', 'LastName'), (2, 'FirstName', 'LastName')
What is the definition of a relational database schema
Tables, columns and relationships that make up a relational database
How to test for equality in PHP between two variables
==
How to test for identity in PHP between two variables
===
how to encrypt a password
$enc_pass = password_hash("password", PASSWORD_DEFAULT);
how to read a file in php
$file = fopen($path, "r"); $contents = fread($file, filesize($path)); fclose($file);
how to write to a file in php
$file = fopen($path, "rw"); fwrite($file, "content"); fclose($file);
How to run sql query
$mysqli = new mysqli("localhost", "user", "password", "db1"); $result $mysqli->query($query); $row = $result->fetch_array(MYSQLI_ASSOC); $result->close(); $mysqli->close();
How to access a global variable
$var = 0; function test() { $GLOBALS["var"] = 1}
How do you create a new MySQL database
CREATE DATABASE [IF NOT EXISTS] dbname1;
How to create a table with an auto-increment primary key, a foreign key, and an indexed archer column
CREATE TABLE Example ( ID INTEGER UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, FOREIGN KEY (ForKeyCol) REFERENCES ForeignTable (ID) ON DELETE CASCADE )
How to create a user on mysql
CREATE USER 'user'@'localhost' IDENTIFIED BY 'password';
A ____________ join Represents the Cartesian product of two tables
CROSS
What are the three pillars of security
Confidentiality Integrity Availability
What MySQL privileges allow users to remove databases, tables, or views?
DROP
What is DDL
Data Definition Language
What is DML
Data Manipulation Language
In database connection string terminology, DSN stands for
Data source name
How to grant privileges to a user on mysql
GRANT ALL PRIVILEDGES ON db1.* TO 'user'@'localhost';
Are PHP functions case sensitive
No
Are global variables visible inside of functions through normal behavior
No, they must be accessed with the global function
You can use the generic _______ functions if you want to use a database that doesn't have a php library
ODBC
What does ODBC stand for
Open Database Connectivity
What does PDO stand for
PHP Data Object
In a database-backend PHP application, the ________ opens a db connection
PHP server
MySQL ______ can speed up query execution as well as protect against SQL injection attacks
Prepared Statements
How to revoke privileges from a user on mysql
REVOKE alter, create, drop ON db1.* FROM 'user'@'localhost'
Which of the following is a php statement that allows you to load a file into your PHP script?
Require
What is an inner join
Return all elements that can be matched both ways between the left and the right tables
What kind of PHP variable stores a single value
Scalar
What is the first step in querying a MySQL db from the web
Validate user input
What is the function name reserved for constructors
__construct($param)
What is the function name reserved for destructors
__construct($param)
Check if a key exists
array_key_exists("key", $array)
How to get the keys of a dict
array_keys($array)
How do you add an element to an array
array_push($array, "value")
How to find the key/index of a search
array_search("value", $array)
Which of the following is a php.ini directive that points to a header file
auto_prepend_file
How to clone an object
by default clone $object will create a shallow clone, implement __clone to achieve a deep copy
How to count the elements in an array
count($array)
A foreign key should have the same or comparable __________ as its related primary key
datatype
how to write a foreach
foreach($array as $value) { stuff($value);}
What is the function of PDO
defines a consistent interface for accessing databases in PHP
PHP string interpolation requires what kind of quotation mark?
double quotes
IN PHP-MySQL connectivity, what is the purpose fo the @ symbol
error suppressor?
What is the use of required_once and included_once
files won't be imported more than once
What files would have to be modified to add authentication to the homework
home_page processAddressUpdate processStatisticsUpdate
What are the differences between htmlspecialchars() function and the htmlentities()
htmlentities covers more characters than htmlspecialchars
How to encode html
htmlspecialchars($html)
How to test if an element is in an array
in_array("value", $array)
What is the role of 'foo' in the php statement function('foo');
its a parameter
PHP variables that are declared inside a function are known as
local
What is the basic PHP library for connection to MySQL
mysqli
A primary key can consist of ______ columns
one or more
how to call a parents version of a method
parent::func()
What is the default PHP class modifier
public
A PHP function that calls itself is known as a ________ function
recursive
What is the difference between include and require
require will throw an error if it doesn't exist
What is a left join
return all elements from the left table and those from the right table who can be matched to something on the left
What is a right join
return all elements from the right table and those from the left table who can be matched to something on the right
What is an alias for the chop() function
rtrim
What is the difference between single and double quotes in php
single quotes takes text 100% literally, while double quotes will interpolate things like \n
The three different PHP sorting functions are
sort - standard sort asort - sort an array, maintaining index association rsort - reverse sort
The php keyword return
stops the execution of a function
in the context of a class, what does the self keyword refer to
the class itself, use it to access static attributes and functions
in the context of a class, what does the $this keyword refer to
the current object itself
How to get GET params from php
the super global $_GET array (dict)
How to get GET params from php
the super global $_POST array (dict)
How to throw an exception in php
throw new Exception($message, $code);
how to raise an error in php
trigger_error($message, $level)
Which command do you use to specify which MySQL db to use
use dbname;
In PHP, the normal way that function parameters are called is known as pass by _________
value
What is the use of the __autoload function
you declare it and define the methodology for finding the file containing the class given the classname as param called when a classname is used and PHP can't locate its declaration