Database Administrator

Resync of MongoDB replica set members Resync of replica set members When the replication fails and lags behind the maximum tolerable range of oplog in primary, the replica set Member changes to stale ). The node cannot catch up with the master node

502nd questions, 053502502. A database is running In ARCHIVBXXMS mode. It has two online redo log groups and each groupHas one member.A lgwr Input/output (I/O) fells due to permanent media failure that has resulted In the loss of redo logFile and

Mongodb Sharding terminology, mongodbsharding ShardingExponential data sharding ClusterA cluster contains multipleShards, EachShardByReplica setComposition CollectionThe table concept in DB, but no schema In sharding scenarios, each collection

256th questions, 053256 256. Sales details are being stored on a daily basis in the SALES_2007 table. A large amount of data isAdded to the table daily. To save disk space, you issued the following command:Alter table sales_2007 compress for all

Mysql query on the sixth day 1, mysql query on the sixth day The general query process is from the client to the server, and there is a network between them. Parse on the server, generate the execution plan, and execute. And return it to the client.

Install and use Memcache I. Resource download You must install libevent before installing memcached. Bytes Decompress the two installation packages to the installation directory (the installation directory is determined by yourself)   Ii. Install

383rd questions, 053383383. At the request of a user, you issue the following command to restore a dropped table: flashback table"BIN $ F2JFfMq8Q5unbC0ceE9eJg = $0" to before drop; Later, the user notifies you that the data inTable seems to be very

425th questions, 053425 425. Which of the following are stored in a transportable tablespace set? (Choose all that apply .)A. The datafiles that make up a self-contained group of tablespaces required for copyB. The system tablespaceC. An export of

Hbase-1.0.1 installation, hbase1.0.1 1. Modify the hbase-site.xml configuration file under the hbase/conf directory and add hbase. rootdir hdfs: // master: 9000/hbase hbase. cluster. distributed true hbase. zookeeper. quorum master, slaves1,

[Oracle], oracle Let's say we are going to develop a application for a bank, or any other enterprise, this application need a DB. And we decide to choose Oracle 12c. Then we make a plan: Application is for WBBANK, so name is WBBANK Application

MySQL multi-Table connection Deletion DELETE is a very careful SQL operation. In general, DELETE operations must be careful to avoid unnecessary losses. DELETE has the following situations: ØDelete from t1 where Condition ØDelete t1 from t1 where

Error code: 1364 error message: Field 'platid' doesn' t have a default value, 1364 platId1. Error description Error code: 1364 error message: Field 'platid' doesn' t have a default valueinsert into 'use'. 't_ platform_scale '() values ()2. Cause of

170th questions, 053170170. ASM supports all but which of the following file types? (Choose all that apply .)A. Database filesB. SpfilesC. Redo-log filesD. Archived log filesE. RMAN backup setsF. Password filesG. init. ora filesAnswer:FG Files

SQLServer: how to search for %, _, [, sqlserver There are two methods: 1. Use ESCAPE to define ESCAPE characters"%" And""And" [] "are considered as wildcards when they appear separately. In order to check whether there are percent signs (%),

Galera source code installation, galera source code --- 1. install the main component on which galera depends # echo "192.168.1.25 db00 db00.mysql.com">/etc/hostsyum-y install cmake gcc-c ++ autoconf automake zlib * libxml * \ ncurses-devel libtool

SQL Server and Oracle query results from multi-row records (datasets) and concatenate a string of SQL statements (vertical table data into spliced text), sqlserveroracle Scenario: For example, you need to query all student numbers whose scores are

View the databases and collections created by sedna, documents, and so on. In the installation directory of sedna, check the cfg directory: [xuzhina @ localhost sedna] $ ls export books_cfg.xml [xuzhina @ localhost sedna] $ ls data/books_files

Error code: 1045 Access denied for user 'skyusers' @ '%' (using password: YES), deniedskyusers1. Error description Grant all privileges on *. * TO root @ "%" identified ". "; 1 queries executed, 0 success, 1 errors, 0 warnings query: grant all

Efficiently traversing InnoDB B + Trees with the page directory -- slot, traversinginnodb Efficientlytraversing InnoDB B + Trees with the page directory1, the purpose of the page directory As described in the posts mentioned above, all records in

Sedna loads xml files and sedna loads xml files Suppose there is an xml file named a. xml, which needs to be loaded into the sedna database xml_db. Sedna loads xml into the database through se_term. There are two methods: 1. Use the-query