Mysql,Oracle数据库连接数简析_MySQL
bitsCN.com
Mysql,Oracle数据库连接数简析 Mysql 01D:/Program Files/MySQL/MySQL Server 5.1/bin>mysql -u root -p02Enter password: ****03Welcome to the MySQL monitor. Commands end with ; or /g.04Your MySQL connection id is 183 05Server version: 5.1.58-community MySQL Community Server (GPL)06 07Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.08This software comes with ABSOLUTELY NO WARRANTY. This is free software,09and you are welcome to modify and redistribute it under the GPL v2 license10 11Type 'help;' or '/h' for help. Type '/c' to clear the current input statement.12-- 使用xuexi数据库13mysql> use xuexi14Database changed15-- 查看字符集16mysql> SHOW VARIABLES LIKE 'character_set%';17-- 控制台汉字乱码,将编码改为gbk,控制台就可以显示中文了18mysql> set character_set_results='gbk';19-- 查看连接数 20mysql> SHOW PROCESSLIST;--100条21mysql> show full processlist;22-- 服务器的状态信息23mysql> show status; Oracle 01SQL> conn / as sysdba02Connected.03-- 连接数04SQL> select count(*) from v$session;05-- 并发连接数06SQL> Select count(*) from v$session where status='ACTIVE';07--最大连接08SQL> show parameter processes;09-- 修改processes和sessions值10SQL> alter system set processes=300 scope=spfile;11SQL> alter system set sessions=300 scope=spfile;
作者 车水码农 bitsCN.com

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

The retention period of Oracle database logs depends on the log type and configuration, including: Redo logs: determined by the maximum size configured with the "LOG_ARCHIVE_DEST" parameter. Archived redo logs: Determined by the maximum size configured by the "DB_RECOVERY_FILE_DEST_SIZE" parameter. Online redo logs: not archived, lost when the database is restarted, and the retention period is consistent with the instance running time. Audit log: Configured by the "AUDIT_TRAIL" parameter, retained for 30 days by default.

The Oracle database startup sequence is: 1. Check the preconditions; 2. Start the listener; 3. Start the database instance; 4. Wait for the database to open; 5. Connect to the database; 6. Verify the database status; 7. Enable the service (if necessary ); 8. Test the connection.

To find the number of occurrences of a character in Oracle, perform the following steps: Get the total length of a string; Get the length of the substring in which a character occurs; Count the number of occurrences of a character by subtracting the substring length from the total length.

The amount of memory required by Oracle depends on database size, activity level, and required performance level: for storing data buffers, index buffers, executing SQL statements, and managing the data dictionary cache. The exact amount is affected by database size, activity level, and required performance level. Best practices include setting the appropriate SGA size, sizing SGA components, using AMM, and monitoring memory usage.

Oracle database server hardware configuration requirements: Processor: multi-core, with a main frequency of at least 2.5 GHz. For large databases, 32 cores or more are recommended. Memory: At least 8GB for small databases, 16-64GB for medium sizes, up to 512GB or more for large databases or heavy workloads. Storage: SSD or NVMe disks, RAID arrays for redundancy and performance. Network: High-speed network (10GbE or higher), dedicated network card, low-latency network. Others: Stable power supply, redundant components, compatible operating system and software, heat dissipation and cooling system.

Oracle can read dbf files through the following steps: create an external table and reference the dbf file; query the external table to retrieve data; import the data into the Oracle table.

The amount of memory required for an Oracle database depends on the database size, workload type, and number of concurrent users. General recommendations: Small databases: 16-32 GB, Medium databases: 32-64 GB, Large databases: 64 GB or more. Other factors to consider include database version, memory optimization options, virtualization, and best practices (monitor memory usage, adjust allocations).

To create a scheduled task in Oracle that executes once a day, you need to perform the following three steps: Create a job. Add a subjob to the job and set its schedule expression to "INTERVAL 1 DAY". Enable the job.
