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  MySQL GROUP BY statement

  MySQL GROUP BY statements GROUP BY statements group result sets according to one or more columns. We can use COUNT, SUM, AVG, and other functions on the grouped columns. GROUP BY syntax SELECT colu

  2022-06-01 15:21:24 Views: 281
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  MySQL5.7- installation based on CentOS6 binary package

  1. Background * MySQL is a relational database management system developed by the Swedish company MySQL AB and currently belongs to Oracle products. MySQL is one of the most popular relational database management systems. In terms of WEB applications, MySQL

  2022-06-01 15:21:24 Views: 290
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  Oracle modifies SID

  Problem description: my default ORACLE_SID was orcl, but now I want to do data synchronization. I have to have a different ORACLE_SID to distinguish it from each other. Now it only takes a few simple steps to modify the ORACLE_SID;1. First

  2022-06-01 15:21:24 Views: 300
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  Oracle12c Operation and maintenance practice Book-the third lesson preparation and precautions before DB installation

  Oracle12c operation and maintenance practice book-the third lesson DB pre-installation preparation and matters needing attention link: https://pan.baidu.com/s/16xMcD7hItWft7JAOh39-Sg password: h7qq

  2022-06-01 15:21:23 Views: 218
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  One-line function on the basis of SQL (7)

  The single-line SQL function has the following categories: the character function numeric function uses the date function. To put it bluntly, it is to add the parameters that meet the definition in the process of using the function, and then execute the function to output the result value. The difference between a single-line function and a multi-line function: the output of a single-line function is

  2022-06-01 15:21:11 Views: 269
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  ALTER SESSION SET EVENTS

  Oracle trace files Oracle trace files are divided into three types, one is the background alarm log file, which records the activities of background processes during database startup, shutdown and operation, such as tablespace creation, rollback segment creation, some alter commands, log switching, error messages, etc.

  2022-06-01 15:21:11 Views: 223
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  Solve MySQL paging data confusion and repetition

  Preface one day, Xiaoming said in a hurry on the communication tool: there is a strange problem on this sideline, please DBA greatly identify, execute the statement select xx from table_name wheere xxx order by field A

  2022-06-01 15:21:11 Views: 235
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  Summary of MySQL client command parameters

  1 mysql syntax: mysql [option] db_name option:-- auto-rehash enable command auto-completion function

  2022-06-01 15:21:11 Views: 268
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  Mysql Ignoring query to other database

  Mysql encounters Ignoring query to other database problem: root@support ~] # mysql-root-p-- socket=/tmp/mysql.sock

  2022-06-01 15:21:10 Views: 258
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  Complete MySQL support for emoji in 10 minutes

  The company has a new requirement that ios clients can use emoji emoticons in online comments. Before mysql 5.5, UTF-8 encoding only supported 1-3 bytes; since MySQL 5.5, it can support 4 bytes of UTF encoding utf8mb4.

  2022-06-01 15:21:10 Views: 241
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  Oracle authorizes a collection of commands to users

  We will start with the creation of the Oracle user rights table, and then learn general actions such as login to give you an in-depth understanding of Oracle user rights allocation control. First, create a sys; / / system administrator with the highest privileges system;// local administrator, times

  2022-06-01 15:21:10 Views: 204
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  Oracle commonly used Export Export commands and performance efficiency comparison

  Oracle import and export commands are mainly EXPDP and IMPDP, EXP and IMP, the difference is as follows: EXP and IMP are client-side tool programs, they can be used not only on the client side, but also on the server side. EXPDP and IMPDP are server-side tools.

  2022-06-01 15:21:01 Views: 223
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  Oracle11g installs example users

  Environment operating system: RHEL 6.4 x86_64DB:oracle 11.2.0.3 is a test library. I forgot to install example when installing and building the library. Sometimes it is not easy to test without these users, for example, there are no scott users.

  2022-06-01 15:21:01 Views: 250
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  Treatment of ORACLE 11204 GRID after CRS disk Group damage

  ORACLE 11204 GRID mainly deals with CRS disks when the CRS disk group (the disk group where ocr and votedisk are located) is damaged. 1. Simulated failure [grid@node1 ~] $oc

  2022-06-01 15:21:01 Views: 233
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  PHP provides Oracle support and adds oci8 module

  Environment: CentOS7 x86_64PHP 7.1.2 (installation path: / usr/local/php7.1.2) Oracle 11G R21. Download the Oracle client: (http://www.oracle.c

  2022-06-01 15:21:00 Views: 251
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  Hang lives when Oracle is turned off (shutdown immediate)

  Two sets of 10.2.0.4 databases produced last night have modified the parameters and need to be restarted. After waiting for about 10 minutes after issuing the shutdown immediate command, the database has not yet been down down. Check the background alert log and find that sh from the beginning

  2022-06-01 15:20:48 Views: 250
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  The libdata1 mysqllog file of Zabbix-Server database mysql is too large

  Today, our zabbix-server machine has been online for half a year, taking up 500 gigabytes of space. I found that the libdata1 file under / var/lib/mysql/ is too large, reaching 300 gigabytes. I immediately thought of zabbix.

  2022-06-01 15:20:48 Views: 252
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  Timing synchronization of tables and data in oracle11g to sqlserver2005 on Winserver2008r2 64-bit system

  Attachment: http://down.51cto.com/data/2367679

  2022-06-01 15:20:47 Views: 301
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  Goldengate merge application process

  When the goldengate application process is split itself, it is best to split it according to the business, otherwise it may cause the application to read data is business confusion, now merge multiple application processes into one application process, the following steps, for reference only: merge replicate application process: 1. Original advance

  2022-06-01 15:20:47 Views: 204
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  Huge Pages and Transparent Hug

  Concept: memory is managed by blocks, known as pages. A page has 4096 bytes. 1MB memory equals 256 pages. 1GB memory equals 256000 pages, and so on. CPU has built-in memory management units that contain these page columns

  2022-06-01 15:20:47 Views: 293