multiple sql statements

four characteristics of the transaction (ACID):  atomicity (atomicity): All operations in a transaction are not divisible atomic units. All operations in a transaction are either successfully executed or all fail.  Consistency (consistency):

1.oracle How does the execution of an SQL statement manage concurrency and recovery control? A syntax-compliant SQL statement that defines the operation of the database. At the moment this operation is executed, a data state for the database is

The jar package provided by the database vendor to manipulate the database is database driven. If individual vendors provide their own database drivers that can lead to a high cost of learning for developers, Sun provides a set of interface

"Learner Management System" 0x04 pymysql database connection optimization write in frontFor Detailed project requirements, see : The "Student management system" of the Django ProjectOptimized Implementationencapsulate the operation into a

Sometimes, we need to insert a lot of data at once or one time to update, delete a lot of data, so in order to improve efficiency, we might as well use the JDBC batch to complete . See below for a small example.Package testbatch;Import

4 Correlation query ( Multi-table Query ) --************** second, related query (multi-table query)****************------ demand: Query employees and their departments ( Show employee name, department name )--2.1 Cross connect query

MySQL and SQL InjectionSQL injection security can occur if you get user-entered data from a Web page and insert it into a MySQL database.This section will show you how to prevent SQL injection and use scripts to filter the characters injected into

Main content :Data Definition Language DDL FocusData manipulation language DML FocusDQL Focus of data query language---transaction control language TCL---database control Language DCL---primary key (primary key)---data redundancy (a separate table

Before using the Pymysql to manipulate the database is written dead in the view function, and there are a lot of duplicate code.We can optimize it and extract the duplicated code. Write function:ImportPymysql#define a database-related configuration

Advantages of applying stored procedures:1. Better performanceStored procedures are precompiled, compile only at creation time, and do not need to be recompiled for each subsequent execution of the stored procedure.Typically, SQL statements are

Sophomore database, just vaguely heard the teacher mentioned the view ah, stored procedures AH, trigger ah what, but just a faint remember the name, and then do small projects, little programs, also no use, are just simple to build tables, related

1. Curriculum ReviewMySQL Basics1) MySQL storage structure: Data SQL statements, tables, database2) Management database:Add: Create database default character UTF8;Delete: Drop database;Modified: ALTER DATABASE default character GBK;Query: Show

First, the JDBC BULK INSERTJDBC BULK INSERT is primarily used for data import and logging because the logs are usually written first in the file.I tested three more common methods with the Mysql5.1.5 JDBC driver, respectively.Method one, using the

Send multiple SQL statements to the databaseCreate DATABASE BatchUse BatchCREATE TABLE Batch_table (ID int primary KEY auto_increment,Name varchar (20))INSERT into batch_table values (NULL, "AAA")INSERT into batch_table values (NULL, "BBB")INSERT

SQL injection security can occur if you get user-entered data from a Web page and insert it into a MySQL database.This blog post will show you how to prevent SQL injection and use scripts to filter the characters injected into SQL.SQL injection, by

The Python SQLite database is a very small embedded open source database software with no independent maintenance process and all maintenance is from the program itself. It uses a file to store the entire database, which is very convenient to

Here's a little bit of knowledge of PHP operating MySQL businessYou know, the default behavior of MySQL is to execute a COMMIT statement after each SQL statement executes, effectively independently of each statement as a single transaction. However,

In the recent project, you need to copy several dump files (text format, 1 ~ 2 GB) records are imported into the mysql database. Due to the large data volume (millions or tens of millions of records ), In the recent project, you need to copy several

The resolution operation saves a parent cursor and child cursor to the library cache and saves them to sga to reuse them and avoid hard parsing. Under what circumstances can I reuse the parent cursor and child cursor?The key information of the

In the MySQL compound-statement SQL background, sending multiple statements to MySQL can reduce the number of network interactions. In case of transactions, the lifetime of transactions on a single thread can be shortened. Writing business logic