handbook/tools/3.Web-Hacking/4.Injection/SQL/Language/SQL-Language.md at 8c056cb3457e46049264dddda6d09ab63e9543c3

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Manipulation

## SELECT

SELECT * (or SOMETHING) FROM table_name;

SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
SOMETHING = Speficy the name of the columns we want to take the information (Columns Name)
FROM = Indicate what table to check --> clause
table_name = EX: Table (Composed of coluns and rows) (Data in form of TEXT, DATE, REAL, ...)
; = end of the statment

SELECT name AS 'Titles'  
FROM movies;

SELECT = Indicate the action (Witch is select) --> clause
name = columns normal name
AS = Change the name of the Column
'Titles' = The name column renamed
- FROM = Indicate what table to check --> clause
table_name = EX: Table (Composed of coluns and rows) (Data in form of TEXT, DATE, REAL, ...)
; = end of the statment

DISTINCT

SELECT DISTINCT tools  
FROM inventory;

SELECT = Indicate the action (Witch is select) --> clause
DISTINCT = Return unique values in the output
tools = Column name
FROM = Indicate what table to check --> clause
table_name = EX: Table (Composed of coluns and rows) (Data in form of TEXT, DATE, REAL, ...)
; = end of the statment

Opperation

SELECT *  
FROM movies  
WHERE imdb_rating > 8;

= != > < >= <=
SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
imdb_rating > 8 = Looking for imdb_rating that is unter 8
; = end of the statment

LIKE

SELECT *   
FROM movies  
WHERE name LIKE 'Se_en';

SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
name = columns
LIKE 'Se_en' = LIKE 'Se_en' is a condition evaluating the name column for a specific pattern.
; = end of the statment

LIKE

SELECT *   
FROM movies  
WHERE name LIKE '%man%';

SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
name = Column name
LIKE = LIKE is a condition evaluating the name column for a specific pattern.
'%man%' = Mean anything that has something before 'man' and something after
; = end of the statment

IS / IS NOT

SELECT name  
FROM movies  
WHERE imdb_rating IS (NOT) NULL;

SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
imbd_rating = columns name
IS (NOT) NULL = Looking for field that are NULL or NOT
; = end of the statment

BETWEEN

SELECT *
FROM movies
WHERE name BETWEEN 'D 'AND 'G';

SELECT = Indicate the action (Witch is select) --> clause
- ```
                  = Everything 
```
FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
name = Column name
BETWEEN = Looking for value between 2 elements
'D' AND 'G' = Values we are looking for
IS (NOT) NULL = Looking for field that are NULL or NOT
; = end of the statment

AND

SELECT *   
FROM movies  
WHERE year BETWEEN 1990 AND 1999  
   AND genre = 'romance';

SELECT = Indicate the action (Witch is select) --> clause

                           = Everything

FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
year = Column name
BETWEEN = Looking for value between 2 elements
'1990' AND '1999' = Values we are looking for
AND = Add a condition
genre = 'romance'; = Looking for column genre = romance
; = end of the statment

SELECT *FROM movies
WHERE year > 2014   
OR genre = 'action';

SELECT = Indicate the action (Witch is select) --> clause

                           = Everything

FROM = Indicate what table to check --> clause
movies = Table name
WHERE = Looking for value (following statement)
year = Column name
2014 = Biger the 2014
OR = Add a OR condition
genre = 'action'; = Looking for column genre = romance
; = end of the statment

Order By

SELECT *  
FROM movies  
ORDER BY name ASD,DSC;

SELECT = Indicate the action (Witch is select) --> clause

                           = Everything

FROM = Indicate what table to check --> clause
movies = Table name
ORDER BY = Order by
name = columns name
ASD, DSC = Assendent, Dessendent
; = end of the statment

Limit

SELECT *  
FROM movies  
LIMIT 10;

SELECT = Indicate the action (Witch is select) --> clause

                           = Everything

FROM = Indicate what table to check --> clause
movies = Table name
LIMIT 10 = Limit the number of responses to 10 (In this case)
; = end of the statment

Case

SELECT name,  
CASE  
  WHEN imdb_rating > 8 THEN 'Fantastic'  
  WHEN imdb_rating > 6 THEN 'Poorly Received'  
  ELSE 'Avoid at All Costs'  
END  
FROM movies;

SELECT = Indicate the action (Witch is select) --> clause
name = Column name
CASE = Only show element that correspond to specific CASE WHEN = Condition ELSE = Everything that does not fit in those condition
END = End the case statement
FROM = Indicate what table to check --> clause
movies = Table name
; = end of the statment

## Join

SELECT *  
FROM orders  
JOIN customers  
  ON orders.customer_id = customers.customer_id;

SELECT = Indicate the action (Witch is select) --> clause

                           = Everything

orders = Table
JOIN = Join to the other table
customer = Second table (the one we merge in)
ON = Explain what field are the same (to add the right info the right customer)

## CREATE

CREATE TABLE table_name (  
   id INTEGER,  
   name TEXT,  
   age INTEGER  
);

CREATE = Indicate the action --> *`clause
TABLE = Specify the table
table_name = EX: Table (Composed of coluns and rows) (Data in form of TEXT, DATE, REAL, ...)
id, name, age = Indicate the name of the columns
INTEGER, TEXT, ... = Indicate the type of value that will be incerted
; = end of the statment

## INSERT

INSERT INTO celebs (id, name, age)  
VALUES (1, 'Justin Bieber', 22);

INSERT INTO = Indicate the action (Add info to a table) --> *`clause
(id, name, age) = Identifying the columns that data will be inserted into.
VALUES = Specify the value that will be inclouded in the table --> *`clause
(1, 'Justin Bieber', 22) = Value included
; = end of the statment

## ALTER

ALTER TABLE celebs  
ADD COLUMN twitter_handle TEXT;

ALTER TABLE = Indicate the action (change the structure of the database) --> *`clause
celebs = Table selected
ADD COLUMN = Specify to add a columns --> *`clause
twitter_handle = Name of the column added
TEXT = Type of element in this column
; = End of the statment

## Update

UPDATE celebs  
SET twitter_handle = '@taylorswift13'  
WHERE id = 4;

UPDATE = Indicate the action --> *`clause
celebs = table selected
SET = Action --> *`clause
twitter_handle = Column name
= '@...' = Input to be added
WHERE id equal 4 = Searching for id equal 4
; = End of the statment

## Delete

DELETE FROM celebs  
WHERE twitter_handle IS NULL;

DELETE = Indicate the action
FROM = Indicate what table to check --> *`clause
celebs =
WHERE = Searching for --> *`clause
twitter_handle = Column Name
IS NULL = Equal Nothing (Empty) --> *`clause
; = End of the statment

## Constraints

Reject & accept specific data

CREATE TABLE celebs (  
   id INTEGER PRIMARY KEY,  
   name TEXT UNIQUE,  
   date_of_birth TEXT NOT NULL,  
   date_of_death TEXT DEFAULT 'Not Applicable'  
);

1. PRIMARY KEY columns can be used to uniquely identify the row. Attempts to insert a row with an identical value to a row already in the table will result in a constraint violation which will not allow you to insert the new row.

2. UNIQUE columns have a different value for every row. This is similar to PRIMARY KEY except a table can have many different UNIQUE columns.

3. NOT NULL columns must have a value. Attempts to insert a row without a value for a NOT NULL column will result in a constraint violation and the new row will not be inserted.

4. DEFAULT columns take an additional argument that will be the assumed value for an inserted row if the new row does not specify a value for that column.

Function

## Count

SELECT COUNT(*)  
FROM table_name;

SELECT = Indicate the action (Witch is select) --> clause
COUNT() = Count the number of row in the column (star) = ALL --> *`clause
FROM = Indicate what table to check --> clause
table_name = table name
; = End of the statement

## Sum

SELECT SUM(downloads)  
FROM table_name;

SELECT = Indicate the action (Witch is select) --> clause
SUM(downloads) = Check the summury of the download column --> *`clause
FROM = Indicate what table to check --> clause
table_name = table name
; = End of the statement

## Max / Min

SELECT MAX(downloads)  
FROM Table_name;

SELECT = Indicate the action (Witch is select) --> clause
MAX(downloads) = Check the maximum download (Highest value) --> *`clause
FROM = Indicate what table to check --> clause
table_name = table name
; = End of the statement

## Average

SELECT AVG(downloads)  
FROM fake_apps;

SELECT = Indicate the action (Witch is select) --> clause
AVG(downloads) = Check the average download --> *`clause
FROM = Indicate what table to check --> clause
table_name = table name
; = End of the statement

## Round

SELECT ROUND(price, 0)  
FROM fake_apps;

SELECT = Indicate the action (Witch is select) --> clause
ROUND(price, 0) = round the price value with 0 precision value after the decimal
FROM = Indicate what table to check --> clause
table_name = table name
; = End of the statement

## Group By I

SELECT year,  
   AVG(imdb_rating)  
FROM movies  
GROUP BY year  
ORDER BY year;

SELECT = Indicate the action (Witch is select) --> clause
year, AVG(imdb_rating) = columns
FROM = Indicate what table to check --> clause
movies = Table
GROUP BY year = Group elements by years
; = End of the statement

## Group By II

SELECT category,  
   price,  
   AVG(downloads)  
FROM fake_apps  
GROUP BY category, price;

SELECT = Indicate the action (Witch is select) --> clause
year, AVG(imdb_rating), ... = columns
FROM = Indicate what table to check --> clause
movies = Table
GROUP BY category, price = Group elements by category and price
; = End of the statement

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