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  How does MYSQ define table and field aliases?

  Aliasing a table when the table name is particularly long, it is inconvenient to use the table name directly in the query. At this point, you can give the table an appropriate alias. Example: SELECT * from info i where i.agequery 33; query result: alias the field as query data

  2022-06-01 18:28:03 Views: 282
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  How to solve the problem of NET HELPMSG 353 when configuring mysql decompressed version

  Below, I would like to tell you briefly about the configuration of mysql decompressed version of NET HELPMSG 353 how to solve, have you known about similar topics before? If you are interested, let's take a look at this article. I believe that NET will appear after reading the mysql decompression version.

  2022-06-01 18:28:01 Views: 226
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  A complete Collection of ORACLE date-time functions

  ORACLE date-time function complete TO_DATE format (time: 2007-11-02 13:45:25 as an example) Year:yy two digits two-digit year display value: 07yyy three digits three-digit year

  2022-06-01 18:28:00 Views: 282
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  Causes and Solutions of CPU load increase after MongoDB upgrade

  Recently, after a three-shard cluster was upgraded from version 3.2 to version 4.0, the CPU load of the cluster node increased a lot (10%-> 40%). Except for the version upgrade, the project logic and operation volume remained unchanged. Close Balancer to

  2022-06-01 18:28:00 Views: 291
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  [oracle11g] DML operation

  1. View all tables select table_name from user_tables;select * from tab

  2022-06-01 18:28:00 Views: 274
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  View the information under the current user of Oracle (user, table view, index, tablespace, synonym, etc.)

  1. Users view the default tablespace of the current user SQL > select username,default_tablespace from user_users; to view the role of the current user SQL > select * from us

  2022-06-01 18:27:59 Views: 251
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  The selection of three Database engines in Mysql

  When we create the database, some small projects will not pay much attention to the database engine, and some large projects will consider the problem of the database engine, which will directly affect the later use. MyISAM:MyISAM is MySQL's ISAM extension format and default database engine

  2022-06-01 18:27:50 Views: 293
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  Oracle series: (17) create tables and constraints

  Review MySQL create table statement users (id integer / name string / birthday date type, default) drop table if exists users;create table users (id I

  2022-06-01 18:27:50 Views: 225
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  4. SQLMY-create a score sheet and insert data into the table

  -- create a score sheet and insert data create table SC (Scid varchar (10), Cid varchar (10), score decimal (18Power1)) into the table-- insert data insert into the table

  2022-06-01 18:27:49 Views: 204
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  How to deal with the failure of inserting rare words in MySQL

  Recently, the business side reported that the insertion of individual user information failed, and the error message was similar to "Incorrect string value:"\ xF0\ xA5. "look, this prompt should be caused by the fact that the character set does not support a rare word. Here is the reply in the virtual machine.

  2022-06-01 18:27:46 Views: 207
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  Oracle database migration

  PL/SQL Release 11.2.0.4.0-Production export version, database address 10.36.40.53PL/SQL Release 11.2.0.4.0-Production import version

  2022-06-01 18:27:46 Views: 258
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  BGP-CX test

  [note] the BGP comprehensive test is the initial configuration of the classroom experiment of teacher Ande in Qianyitang, which is sorted out by myself: all devices are equipped with interface IP address, all equipment ring return address is xx.1.1.1/32 bit EBGP experiment: [participating equipment: R1/R2/R4/R5] on R1, check

  2022-06-01 18:27:41 Views: 222
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  Summary of some important concepts and data types of database (reading notes)-- python

  Some concepts of the database: what is the primary key of 1.1.PRIMARY KEY: a unique key composed of one or more columns in a table, that is, one or more columns can uniquely identify a record (normally implemented in one column). Features: 1. The column of the primary key cannot contain a null value N

  2022-06-01 18:27:40 Views: 281
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  Syntax for creating temporary tables

  Create global temporary table temp_tab_name (column datatype [, column datatype]) [on commit {delete | pres

  2022-06-01 18:27:40 Views: 246
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  3.5-MongoDB replica set test

  * MongoDB replica set test main build library, build collection > use mydb # build library > db.acc.insert ({AccountID:1,UserName: "123", password:" 123456 "}) # insert

  2022-06-01 18:27:40 Views: 265
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  Uninstall Oracle 11g for Oracle learning

  After the installation of Oracle 11g, if there is a need to uninstall. You can do the following: manually delete the directories, files, etc., established during the Oracle installation. This approach is feasible for Linux, but the Window version involves services, registries, and so on. Often deleted

  2022-06-01 18:27:40 Views: 284
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  Undolog redolog binlog

  The difference between redo and binlog: 1, the first two are to record the change of data, the difference is that binlog records the change information of all data, while innodb's redo log only records the change of all innodb table data. 2. Binlog is a record

  2022-06-01 18:27:39 Views: 286
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  Invalid user.table.column, table.column or column description-solution

  The reason for this problem is that when you use the wrong field name or oracle keyword, even if you want to rename or delete this field, you will find the solution to this error all the time: add double quotation marks to the field you want to delete or update, and you will not report an error, so you can delete it and start again or fix it.

  2022-06-01 18:27:39 Views: 288
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  Failure encountered in installing zabbix

  Failure 1: the following problems occurred when compiling zabbix. The compilation parameters I used are as follows:. / configure-- prefix=/home/zhanjun/tools/zabbix-2.4.7/-- enable-serv

  2022-06-01 18:27:39 Views: 220
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  Automatic initialization of SQL Server 2017 AlwaysOn AG (5)

  Temporarily preventing the primary copy from setting more database seeds to the secondary copy can deny the availability group permission to create the database. Execute ALTER AVAILABILITY GROUP [] DENY CREATE ANY DATABASEG on the secondary copy

  2022-06-01 18:27:39 Views: 202