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  Redis learns 8Murray-persistence-related testing AOF method

  1. Shutdown service or kill the process to test whether data is lost. Turn off RDB persistence, start AOF persistence, and restart redis service. Set the value 127.0.0.1 6379 > mset K1 v1 K2 v2OK127.0.0.1

  2022-06-01 22:09:33 Views: 217
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  MySQL logs in locally using IP instead of socket

  # # specify hostname and port as a matter of course. Failed [root@mysql01 ~] # / opt/mysql/bin/mysql-uroot-h localhost-P 3307-pEnter

  2022-06-01 22:09:33 Views: 298
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  External table of Dameng database

  An external table is a table that does not exist in the database. By providing Damon with metadata that describes external tables, we can access an operating system file as if it were a read-only database table, as if the data were stored in a normal database table. External tables are an extension of database tables. Create

  2022-06-01 22:09:15 Views: 218
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  SQL Server query optimization and transaction processing

  It is the most basic to understand and master the sentence operation of adding, deleting, changing and querying SQL. In the actual production environment, we will also use some more advanced data processing and queries, including indexes, views, stored procedures and triggers. This blog mainly focuses on how to better realize the operation, diagnosis and optimization of the database.

  2022-06-01 22:09:15 Views: 251
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  MGR needs to use a primary key

  Validating the MGR schema table requires a primary key, otherwise inserting data will report an error. Mysql > show tables;+-+ | Tables_in_dd | +-+ | a

  2022-06-01 22:09:15 Views: 219
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  Basic mysql operations-removing duplicates, taking field names, query expressions, constants, etc., and the + sign

  Query constant value SELECT 100; # display constant value SELECT 'bitch'; # display string constant, query expression SELECT 100% 99% select 100% 99 in single quotation marks; query function SELECT

  2022-06-01 22:09:14 Views: 298
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  Deploy MongoDB sharding cluster

  Deploying MongoDB sharding Cluster sharding Overview Database applications with high data volume and throughput will cause great pressure on stand-alone performance, large query volume will deplete stand-alone CPU, large amount of data will have greater pressure on stand-alone storage, and will eventually deplete system memory and transfer the pressure to disk IO

  2022-06-01 22:08:47 Views: 205
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  Similarities and differences between char and varchar2

  The preface happened to encounter this knowledge point when preparing for the exam recently. I think that the differences between char and varchar2 can be distinguished from the three criteria (space complexity, time complexity, stability) of the evaluation algorithm, just mark. Char and varchar2 are both used to store words.

  2022-06-01 22:08:47 Views: 274
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  HBase error ERROR: org.apache.had

  When learning hbase, set up the environment and start the hbase,jps viewing process to find that hmaster and hregionserevr can appear normally. After entering hbase shell under the terminal, you can also enter the shell of hbase and enter List

  2022-06-01 22:08:46 Views: 216
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  Common errors in MHA and their Solutions

  Error 1 runs masterha_check_repl-- conf=/etc/masterha/app1.cnf error Testing mysql connection and privileges.

  2022-06-01 22:08:45 Views: 210
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  Summary of database paradigm

  1NF: each column of a database table is an indivisible basic data item. Analysis: there are no multiple columns that represent the same property; the value of a column cannot be a collection. It is almost impossible to represent an one-to-many relationship as multiple attributes of a table or multiple values of an attribute. Solution: create a new table with "1" as the new table's

  2022-06-01 22:08:45 Views: 201
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  Oracle History SQL executes time-consuming queries

  This query must first understand the dba_hist_sqlstat view, that is, not all SQL can be queried in dba_hist_sqlstat: DBA_HIST_SQLSTAT displays historical

  2022-06-01 22:08:45 Views: 245
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  Migration of MySQL databases across partitions

  1. Requirements analysis MySQL database has one master and two backups, but not in the same partition. The so-called partition means that the data is stored on different storage, in order to prevent data loss caused by storage failure. Second, the solution, the data migration migrates the data through the reserve database, does not move the main database, does not affect the business. Operation step

  2022-06-01 22:08:44 Views: 235
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  SQLite Runtime restrictions (Run-time Limits)

  Excerpt from: http://www.sqlite.org/c3ref/limit.htmlint sqlite3_limit (sqlite3*, int id, intnewVal); this interface allows you to connect

  2022-06-01 22:08:44 Views: 237
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  SQL Server insider analysis plan

  For Analyzing plans analysis plans to really understand query plans and really find, fix, or solve problems with query plans, you need to have a solid understanding of the query operations that make up these plans. Overall, there are too many operators who can discuss them in one chapter. In addition

  2022-06-01 22:08:35 Views: 239
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  MariaDB 10.3 Primary semi-synchronous replication

  MariaDB master semi-synchronization, that is, both master-slave synchronizations enable semi-synchronous replication. one。 MariaDB01 master MariaDB02 from enabling semi-synchronous replication 1. MariaDB01 master SET GLOBAL rpl_semi_syn

  2022-06-01 22:08:23 Views: 236
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  MySQL Optimization (Super complete version) (1)

  1. Optimization of MySQL preface:     MySQL database optimization module:  -database design-three paradigms  -database indexes: unique index, primary key index, aggregate index, composite index, default index  -

  2022-06-01 22:08:04 Views: 233
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  Oracle_RAC_12C Management and practice

  Oracle12C official documents: download Oracle12C software from the official website: download it from the official website and try it for free; High availability: business will not be interrupted and data will not be lost, as measured by SLA indicators; used to deal with planned upgrade maintenance and unplanned fault light scenarios; MAA:

  2022-06-01 22:08:04 Views: 249
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  Cases of common sentences in mysql

  1. Description: create database CREATE DATABASE database-name2, description: delete database drop database dbname3, description: backup sql server--- create backup data d

  2022-06-01 22:08:03 Views: 241
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  Setting up mongo Cluster by docker

  Author: who has amnesia link: http://www.jianshu.com/p/4d86e9c33e0d Source: the copyright of the short book belongs to the author. Commercial reprint please contact the author for authorization, non-commercial reprint please indicate the source.

  2022-06-01 22:07:42 Views: 265