10-3 B1-5 query customer's order
Find the order status of the customer, which is displayed as: customer ID, company name, order ID, employee ID
select customers.CustomerID,customers.CompanyName,orders.OrderID,orders.EmployeeID
from customers,orders
where orders.CustomerID=customers.CustomerID and orders.ShipCity=customers.City
ord ...
Posted by shortysbest on Tue, 16 Jun 2020 04:20:18 +0200
Ten suggestions for Java exception handling
Preface
Ten suggestions for Java exception handling, I hope to help you ~
This article has been uploaded to github:
https://github.com/whx123/Jav...
Public number: A little boy collecting snails
First, try not to use e.printStackTrace(), but to use log printing.
Counterexamples:
try{
// do what you want
}catch(Exception e){
e.printStackTr ...
Posted by sheilam on Mon, 15 Jun 2020 18:07:36 +0200
Mysql enable slow query and log analysis
1, Why open slow query
Most of the reasons for the poor query performance are the large amount of data. To start the slow query of mysql and record the SQL statements that take a long time to query in the log is conducive to our better position and optimization.
2, Several common reasons for the ...
Posted by bg on Sun, 14 Jun 2020 05:47:10 +0200
[Huawei Cloud Technology Sharing] Database Development: MySQL Seconds_Behind_Brief Master Analysis
[Summary] For mysql primary and standby instances, seconds_behind_master is an important parameter to measure the delay between master and slave.Seconds_can be obtained by executing "show slave status;" on slaveBehind_The value of master.
Seconds_Behind_Master
For mysql primary and standby instances, seconds_behind_master is an impor ...
Posted by heldenbrau on Fri, 12 Jun 2020 06:20:43 +0200
pikachu range clearance WP
pikachu range clearance WP
brute force
Brute force solution based on form
Verification code bypass (on server)
Verification code bypass (on client)
token anti explosion?
Cross-Stie Scripting
Reflective xss(get)
Reflective xss(post)
Storage xss
Dom xss
Dom xss-x
XSS blind play
XSS filtering
htmls ...
Posted by Delaran on Thu, 11 Jun 2020 09:42:01 +0200
JSON type of new MySQL 5.7 features
With the wide application of NOSQL database, the extensible storage mode also has a good support in relational database. A new data type, JSON, has been added in MySQL 5.7
JSON data type meaning
In fact, without the support of JSON data type, we can save the data in this format by varchar type or text type, but why do we need to specifica ...
Posted by poppy on Wed, 10 Jun 2020 08:47:33 +0200
How to use Node+MySQL+express to add, delete, modify and query
First of all, thank you for this little sister's video: Bili bilibili - very poor female programmer
List structure attached:
1, Development preparation
Node installation and configuration
MySQL installation and configuration
Database visualization tools: Navcat
Interface t ...
Posted by ukspudnie on Tue, 09 Jun 2020 07:08:23 +0200
Hundreds of billions of warehouse projects (warehouse theory_ Product dimension data loading (zipper table))
Product dimension data loading (zipper table)
Zipper watch design:
1. Collect the full data of the day and store it in the ND (current day) table.
2. You can take out yesterday's full data from the history table and store it in the OD (last day's data) table.
3. ND-OD is the data added and changed on ...
Posted by eagle1771 on Fri, 05 Jun 2020 06:27:04 +0200
Cases of data inconsistency caused by MySQL implicit type conversion
1.1 problem description
. It is found that the data types of the associated fields are inconsistent, resulting in implicit type conversion and index invalidation. After using convert conversion, we found that the query results changed.
Ta ...
Posted by dabbott on Fri, 05 Jun 2020 06:09:46 +0200
SOD Honey for.NET ORM--Introduction to Zero Foundations
PDF.NETThe SOD framework is not only an ORM, but its ORM function is unique. I have introduced it many times in the blog, but it is all theoretical. Many beginners may still feel complex. In fact, the ORM of SOD is very simple.Let's take a step-by-step look at the popular Code First approach.
I. Preparations
1.1, add SOD package reference
...
Posted by mandrews81 on Thu, 04 Jun 2020 02:09:52 +0200