Database Administrator

Oracle cascade operations When you add a foreing key constraint, you can also specify the cascade operation type, which is mainly used to determine how to process the foreign key fields in the subtable When deleting a record in the (on delete)

Record is locked by another user, recordlocked This error is reported when data is updated: The table is locked because no commit exists during table operation. You can unlock the row lock by executing the following two statements.View the sid

Import a text file to the mysql database table and insert command to insert data to the table, mysqlinsert 1. Import a text file to a database TABLE: mysql> load data local infile 'text path 'into TABLE name; example: mysql> load data local

LeetCode OJ Employees Earning More Than Their Managers, leetcodeoj TheEmployeeTable holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id. + ---- + ------- + -------- + ----------- +

Database optimization tutorial (6) index-related operations, tuning IndexesIii. Index 3. Index-related operations In the previous section, we introduced the functions and types of indexes. This section describes the operations related to indexes! 1)

Run scripts to transfer dynamic SQL statements and Report SQL statements. In most cases, the SQL statements of the report data source are fixed, but sometimes some of them need to be dynamically spelled out, for example, in a report application, you

Database Tuning tutorial (2) Prepare slow query data and optimize Databases 1. Slow query found In the previous section, we talked about the definition of slow queries. This section describes how to create a large table and prepare data for slow

Database Tuning tutorial (9) index TuningIii. Index 6. Several Common possibilities of indexing but not being used I talked about when to avoid using indexes, but sometimes I don't know how to use indexes. Below are several cases where indexes

A small example of grouping and summation in oracle Cold weather in April 9, 2015Table gw_log is designed as follows: Name Type Nullable Default Comments ------------ ----------- -------- ------- ---------- ID VARCHAR2 (50) Message id SERVICE_ID

Project Database Design and Project Database Design The database system is not only designed once. I was designed during this interview, so I once again flipped out the textbooks I used to take the test and made some new discoveries in the database

Use sqlserver to sequentially number each group of records. Use sqlserver to sequentially number each group of records Project business needs to number each group of records to help you locate a specific row for each person when performing column

Ubuntu MongoDB 32-bit installation, tumongodb Download 32-bit MongoDB: https://fastdl.mongodb.org/linux/mongodb-linux-i686-3.0.1.tgz Unzip: tar-zxvf/mongodb-linux-i686-3.0.1.tgz Go to the MongoDB directory Create two files Mkdir data // store

Run scripts to generate reports of hybrid data sources and reports. You can use different data sources in the same report, such as RDB, TXT, Excel, JSON, HTTP, Hadoop, and mongodb. If you use a hybrid data source in a computing report that does not

[Translated from mos] monitors the progress of the flashback database,Monitor the progress of the flashback databaseReference:How to determine flashback database progress (Doc ID 1071391.1)Applicable:Oracle Server-Enterprise Edition-Version 10.1.0.2

Mariadb introduction, mariadb 1. Introduction to mariadb Official Website: https://mariadb.orgMariaDB was developed by Michael Widenius, MySQL founder. He sold his own company MySQL AB to SUN for $1 billion, as SUN was acquired by Oracle, the

Article Title, article title Daquan Oracle 11gR2 Clusterware log location:All clusterware daemon logs are stored in the/log/directory. The directory structure is as follows:Alert. log-check this article for most clusterware problems../Admin:./Agent:

Enq: DM, resetlogsenq In recent cases, the alter database open resetlogs command in db 10.2.0.5.12 has been waiting, and the alert_sid.log information is: Setting recovery target incarnation to 2   The waiting event obtained from v $ session.

How to backup and restore database in SQL Server, backuprestore /* By Dylan SUN */ If you want to backup and restore one database in SQL Server. Firstly, create a shared folder, and add everyone with read/write right. Secondly, backup your

Use of database indexes and database Indexes I found a problem today. The problem is probably like this. I can query the interface information and use the local database locally for access. However, the access speed will be very busy after being

Getting started with mysql enterprise backup, enterprisebackup **************************************** * ********************** -- 1. full backup *************************************** * ******************** # mysqlbackup -- defaults-file