I believe that many front-end players will find it tedious or even difficult to connect to sql using Node.js at first.Don't be afraid!TypeORM helps you solve all the questions about operating sql!
This article is intended as an amniotic action and does not describe the use of TypeORM in detail. If necessary, please visit Official Web pe ...
Posted on Sat, 07 Dec 2019 22:07:27 -0500 by lancia
To test the scenario when the following system table OBJ $has bad blocks, can the database automatically repair the bad blocks?
(I) database environment
# Database version
sys@ORCL> select * from v$version;
Oracle Database 11g Enterprise Edition Release ...
Posted on Sat, 07 Dec 2019 21:57:53 -0500 by stuartshields
In the last article, we used the JdbcTemplate to access the database. After all, we used the native SQL form. I'm sure that lazy people like me won't consider it..
This record uses JPA to greatly reduce our code volume
First, prepare the SQL file
DROP TABLE IF EXISTS users;
CREATE TABLE users (
id INT ( 11 ) PRIMARY KEY AUTO_INCR ...
Posted on Sat, 07 Dec 2019 19:49:01 -0500 by alwoodman
Characteristics of invisible index
The indexes created by default are visible. If you need to create an invisible index, you need to specify the invisible parameter.
The invisible index index cannot be used by default. You need to turn on the parameter optimizer switch ='use invisible indexes = on 'to use it;
If force index is used, it c ...
Posted on Sat, 07 Dec 2019 14:44:45 -0500 by LikPan
At about 9:30 in the morning, the salesperson reported that their page was opened slowly, and the subsequent page appeared 502.
Then I receive the alarm and log in to the database server to check the cpu 400% load 30 or so
Enter the database and find many slow queries
It was thought that these slow queries came from the daily scheduled task ...
Posted on Sat, 07 Dec 2019 13:28:38 -0500 by Liquix
MySQL indexes and transactions, views, storage engines MylSAM and lnnoDB
The concept of index
Indexes in databases are similar to catalogs in books:
1. - In this book, you don't have to read the whole book to use the catalog to quickly find the information you need.2. The table of contents in the book is a list of words with page numbers cont ...
Posted on Sat, 07 Dec 2019 03:42:09 -0500 by BigMike
This paper introduces how to establish a jdbc connection for database query.
Create a java project and import the jar package.
Using mysql database, the author needs mysql database driver jar package and jdbc connection jar package to establish jdbc connection.
The process of establishing a jdbc connection is as follows:
1. Load database d ...
Posted on Sat, 07 Dec 2019 02:08:08 -0500 by Barb54
The development of an insert SQL is a scheduled task. The content is as follows. It needs to be executed about 5-10 times a day. After running for a while from the select part, the author gives up and has no result. The efficiency is very poor
INSERT INTO bs_sf_yd_flow_check (
Posted on Fri, 06 Dec 2019 13:29:05 -0500 by semlabs
JDBC creation process
Load database driver
Create database connection
Create operation command
Execute SQL statement
Process return result set
Close result set
Close operation command
First load the driver
Project right click to find Open Module Settings open
After opening, do the following
Posted on Fri, 06 Dec 2019 13:23:39 -0500 by snowdog
Someone in the community asked: C ා cannot call the return value of the custom function in Oracle normally. But in PL/SQL, the normal call returns.
So let's try:
1. Preparation function (Oracle 11g. 22.214.171.124)
CREATE OR REPLACE FUNCTION F_Update_Grade(v_UserID in Number)
return nvarchar2 is
V_Grade := ' ...
Posted on Fri, 06 Dec 2019 08:23:47 -0500 by plapeyre