current

Question 1

are strings mutable or immutable in java and why

Answer 1

immutable.

because of security issues, minimize memory

Question 2

what is a string

Answer 2

a data type that represents text

Question 3

name 3 string methods

Answer 3

lenght
concat
charA

Question 4

sql create table

Answer 4

CREATE TABLE table_name

Question 5

sql RDMS

Answer 5

program that allows you to create, update, and administer a relational database

Question 6

sql how to select all tables + rows

Answer 6

SELECT * FROM table_name

Question 7

sql what does WHERE do

Answer 7

allows you to filter a result based on a condition

eg SELECT * FROM Customers
WHERE Country = Mexico
————————–
SELECT column1, column2, columnN

FROM table_name

WHERE [condition]

Question 8

sql retrieve data from table

Answer 8

SELECT x FROM y

Question 9

SQL truncate vs drop

Answer 9

truncate dels data from table but not table itself

drop dels table.

Question 10

sql what is join

list joins and describe

Answer 10

• combines records from 2 or more tables.
• inner join
• left join
• rt join
• full join

inner - returns rows having matching values in both tables.
left - returns all rows from left table and matching rows from rt table.
right- returns all rows from rt table and matching
full - returns all rows from left and rt table

Question 11

primary key vs foreign key

Answer 11

primary key uniquely identifies each record in a db.

foreign key links two tables together

Question 12

sql select all tables from a specific db

Answer 12

SELECT * FROM db_name

Question 13

sql create dbase

Answer 13

CREATE DATABASE database_name

Question 14

sql create table

Answer 14

CREATE TABLE table_name

Question 15

sql alter table

Answer 15

adds, deletes, or modifies columns in a table
ALTER TABLE table_name

ALTER TABLE Customers
DROP COLUMN ContactName; // deletes col

Question 16

what is sql

Answer 16

structured qurey lang. let’s you access and manipulate dbs.

Question 17

relational database management system

Answer 17

is a program used to maintain a relational database

Question 18

relational database

Answer 18

The tables are related to each other - based on data common to each.

Question 19

sql statements

Answer 19

(TABLE) DDL - Data Definition Language - CREATE, ALTER, DROP

(DATA) DML - Data Manipulation Language - SELECT, INSERT, UPDATE, DELETE

(PERMISSIONS) DCL - Data Control Language - GRANT, REVOKE

(TRANSACTIONS) TCL - Transaction Control Language - SAVEPOINT, ROLLBACK, COMMIT

Question 20

sql create primary key

Answer 20

ALTER TABLE table_name ADD PRIMARY KEY (ID)

Question 21

sql insert

Answer 21

inserts new rows
INSERT INTO TABLE_NAME (column1, column2, column3,…columnN)

VALUES (value1, value2, value3,…valueN);

Question 22

sql update

Answer 22

update existing rows

UPDATE Customers
SET ContactName = ‘Alfred Schmidt’, City= ‘Frankfurt’
WHERE CustomerID = 1;

Question 23

ccs how to change background color

Answer 23

body{ background-color: red}

Question 24

name 5 html tags

Answer 24

img, body, head, h1, paragraph

Question 25

is js case sensitive

Answer 25

yes.

Question 26

js == vs ===

Answer 26

both check for equality. == does not care about data type while === does. strict equality

Question 27

html how to add image

Answer 27

<img></img>

followed by source to url

Question 28

html

Answer 28

hyper text markup lang > structure

Question 29

css

Answer 29

cascading style sheets > style and placement

Question 30

ways to add css file to html

Answer 30

Inline - by using the style attribute in HTML elements
Internal - by using a element in the section
External - by using an external CSS file
w/in tags

Question 31

html how to link pgs or files

Answer 31

use a tag, href, then url

Question 32

how to add external css to html

Question 33

how are vars declared

Answer 33

var x = 5;

Question 34

css selectors

. 
# 
p 
div, p 
div p
div > p 
div + p

Answer 34

selectors

. class
# id
p selects all p els
div, p selects all div and p els
div p, p w/in div
div > p , selects ps where parent is div
div + p, where ps are immediately after div

Question 35

DS - stack and que

Answer 35

que fifo, data can only be inserted from the rear

stack - lifo data can only be inserted from one side = top

Question 36

array list vs linked list

Answer 36

alist - better for storing and accessing data.

linked list - better for manipulating data. act as a que and list

Question 37

array vs. arraylist

Answer 37

array once created cant change. fixed length.

arraylist - var length can be changed.

Question 38

the collection interface

Answer 38

foundation upon which the collections framework is built. It declares the core methods that all collections will have.

Question 39

map interface

Answer 39

maps unique keys to values. A key is an object that you use to retrieve a value at a later date.

Question 40

set interface

Answer 40

a collection that can’t contain duplicates

Question 41

arraylist

Answer 41

resizable array

Question 42

constructor

Answer 42

initializes object