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Understand the meaning and usage of table partition Master the traditional (10g and before) table partitioning method Master the table partition mode of 11g Allows users to divide a table into multiple partitions Users can execute queries and access only specific partitions in the table Different partitions are stored on different dis ...

1. Introduction to PLSQL helloworld declare #Declaration of variables i integer; #Start of method begin #Similar to Java system out. Println ('Hello world '), put() output; put_lint() line feed output; Dbms_Output.put_line('hello world!'); #Method end end; 2. Variables Common variables in PLSQL programming are divided into two ...

1: Cartesian product problem 1. Cartesian product: all records in multiple tables will match each other once. For example, if there are m records in Table 1 and n records in Table 2, Cartesian product will produce m*n records, such as select * from table 1 and table 2 2. In order to avoid Cartesian product, you can add effective connection con ...

1, select statement Overall form of Select statement: select col1, col2... // Column name to find from table_name // Which table do you want to search where condition // Set search criteria group by col... // Set grouping having condtion // Set grouping conditions order by col... // Set sort The following examples illustrate the specific u ...

The difference between Oracle and Mysql 1, Main differences 1. Software specification: Oracle is a large database, which occupies a lot of memory;Mysql is a lightweight database, which is lightweight and occupies less memory; ps: I pulled the image of the two with docker. mysql is 545M in size, while oracle11g requires 6.85G 2. Expenses: ...

Use tools to understand global information (awr, awrdd, addm and other reports) AWR report is often the most famous tool for overall analysis of oracle. Few people may use other reports. Although the AWR report information is detailed, if it is not for deep experience, some difficult and miscellaneous diseases may not be located quickly by rel ...

First of all, don't use the default service for the client connection, that is, the connection used by the application. The source of the original text is Real Application Clusters Administration and Deployment Guide: All of these services are used for internal management. You cannot stop or disable any of these internal services to do pl ...

The asset module has a customized report through FA_ The asset module information and accounting information can be obtained by associated query of related tables and Sub Ledger XLA. It takes one hour to run the data of a single asset a / C set in a single month before optimization, and it can be completed in about one second after SQL optimiza ...

Introduction to the Author Author: Lucifer Liu, member of the Chinese DBA Consortium (ACDU).Currently mainly engaged in Oracle DBA work, has been engaged in Oracle database development work, mainly serving the production and manufacturing, Automotive Finance and other industries.Now has Oracle OCP, OceanBase OBCA certification, good at Orac ...

Mainly based on w3school sql (because it is the basis of sql), supplemented by courseware and exercises To prevent you from dying first because you read the wrong address https://www.w3school.com.cn/s.asp select where Query statements, the most commonly used select Listing from Table name where condition The asterisk is equivalent to query ...