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ApsaraDB RDS:Terms

Last Updated:Feb 02, 2024

This topic introduces the terms that are used in ApsaraDB RDS.

A

  • AliSQL

    AliSQL is an independent MySQL branch that is developed by Alibaba Cloud. AliSQL provides all features of the MySQL Community Edition and some similar features that you can find in the MySQL Enterprise Edition. These similar features include enterprise-grade backup and restoration, thread pools, and parallel queries. In addition, AliSQL provides Oracle-compatible features, such as the Sequence engine. ApsaraDB RDS for MySQL with AliSQL provides all features of MySQL and a wide range of advanced features that are developed by Alibaba Cloud. The advanced features include enterprise-grade security, backup and restoration, monitoring, performance optimization, and read-only instances.

    For more information, see Overview of AliSQL features.

  • AliPG

    Alibaba Cloud supports a series of PostgreSQL-compatible cloud database services. These services use AliPG, a database kernel that is developed by Alibaba Cloud. AliPG is compatible with open source PostgreSQL and is put into commercial use in 2015. AliPG supports the mainstream PostgreSQL versions. AliPG has been running stably for years and supports the services inside Alibaba Group and on Alibaba Cloud.

    For more information, see AliPG benefits.

  • security group

    A security group is a virtual firewall that is used to control the inbound and outbound traffic of the Elastic Compute Service (ECS) instances in the security group. After you add a security group to an RDS instance, all ECS instances in the security group can access the RDS instance.

    For more information, see Configure a security group for an ApsaraDB RDS for MySQL instance.

  • pay-as-you-go

    A pay-as-you-go RDS instance is billed per hour based on your actual resource usage. We recommend that you select the pay-as-you-go billing method for short-term use. If you no longer need your pay-as-you-go RDS instance, you can release the RDS instance to reduce costs.

    For more information, see Billable items.

B

  • semi-synchronous mode

    After an update operation originated from an application is complete on a primary RDS instance, the update log record is synchronized to all secondary RDS instances of the primary RDS instance. The update transaction is considered committed after the secondary RDS instances receive the update log record rather than after the update log record is replayed on the secondary RDS instances. If a secondary RDS instance is unavailable or a network interruption occurs between the primary and secondary RDS instances, the semi-synchronous mode degrades to the asynchronous mode.

  • subscription

    A subscription RDS instance is an instance for which you pay an upfront fee. For long-term usage, this billing method is more cost-effective than the pay-as-you-go billing method. You are charged lower prices for longer subscription durations.

    For more information, see Billable items.

  • backup

    For data integrity and reliability purposes, automatic backups must be performed on an RDS instance on a regular basis to ensure that the data of the RDS instance can be restored.

    For more information, see Backup overview.

  • local disk

    In ApsaraDB RDS, local disks refer to local SSDs. Local disks are deployed on the same physical host as the RDS instance to which the local disks are attached. You can store data on local disks to reduce the I/O latency.

    For more information, see Storage types.

C

  • CPU utilization

    CPU utilization indicates the resources that the programs and processes occupy in a database system over a specific period of time.

D

  • DAS

    Database Autonomy Service (DAS) is a cloud service that uses machine learning and expert experience to automate perception, healing, optimization, O&M, and security for databases. DAS simplifies database management and prevents service failures that are caused by manual operations. This way, DAS helps ensure that your database service runs in a stable, secure, and efficient manner.

    For more information, see Overview of DAS.

  • DBS

    Database Backup (DBS) is a cost-effective backup service that helps protect the data in RDS instances.

    For more information, see What is DBS?

  • DMS

    Data Management (DMS) is a GUI-based tool that is developed by Alibaba Cloud. DMS supports data management, schema management, server management, access control, business intelligence (BI) charting, data trend analysis, data tracking, and performance monitoring and optimization. DMS can be used to manage relational databases, such as MySQL, SQL Server, PostgreSQL, MongoDB, and Redis databases. DMS can also be used to manage NoSQL databases and Linux-based database servers.

    For more information, see What is DMS?

  • DTS

    Data Transmission Service (DTS) is a data streaming service that is developed by Alibaba Cloud. DTS can be used to migrate, subscribe to, and synchronize data between relational databases, NoSQL databases, and online analytical processing (OLAP) databases over stable, secure transmission links.

    For more information, see What is DTS?

  • region

    A region is a geographic location in which the RDS instance that you purchase resides. When you purchase an RDS instance, you must specify a region. The region of an RDS instance cannot be changed after the instance is created.

  • read and write QPS

    Read and write QPS indicates the number of INSERT, SELECT, and UPDATE statements that are executed on an RDS instance per second when both read and write requests are allowed.

  • dedicated RDS instance

    A dedicated RDS instance enjoys dedicated CPU and memory resources. The performance of a dedicated RDS instance is guaranteed and is not affected by the other instances that are deployed on the same physical host. In the dedicated instance family, dedicated host instance types have the highest specifications. A dedicated host RDS instance occupies all the resources of the physical host on which the RDS instance is deployed.

    For more information, see Instance families.

E

  • ECS

    Elastic Compute Service (ECS) is a cost-effective, easy-to-use, easy-to-maintain, secure, reliable, and scalable service that is provided by Alibaba Cloud. Each ECS instance runs as a virtual machine in the cloud and provides various flexible configurations. You can run various workloads, such as websites, blogs, games, and applications, on ECS instances. ECS is a popular service that is typically used in tandem with RDS to build applications.

    For more information, see What is ECS?.

  • ESSD

    In ApsaraDB RDS, cloud disks consist of standard SSDs and ESSDs. ESSDs are developed by Alibaba Cloud based on the next-generation distributed block storage architecture. ESSDs deliver ultra-high storage performance. ESSDs are integrated with 25 Gigabit Ethernet and remote direct memory access (RDMA) technologies. ESSDs can help you reduce one-way latencies and process up to 1 million read and write requests at random per second. ESSDs come in three performance levels (PLs):

    • PL1 ESSD: This is the basic PL of ESSDs.

    • PL2 ESSD: A PL2 ESSD delivers input/output operations per second (IOPS) and throughput that are approximately twice the IOPS and throughput delivered by a PL1 ESSD.

    • PL3 ESSD: A PL3 ESSD delivers IOPS that is up to 20 times the IOPS delivered by a PL1 ESSD. A PL3 ESSD also delivers throughput that is up to 11 times the throughput delivered by a PL1 ESSD. PL3 ESSDs are suitable for business scenarios in which highly concurrent requests must be processed with high I/O performance and at low read and write latencies.

    For more information, see Storage types.

F

  • service account

    The service account of an RDS instance is used by Alibaba Cloud technical support engineers to troubleshoot issues on the RDS instance. If Alibaba Cloud technical support engineers need to perform operations on an RDS instance during the troubleshooting process, you must grant permissions to the service account of the RDS instance. After the validity period of the authorization ends, the temporary service account is automatically deleted.

    For more information, see Grant permissions to the service account of an ApsaraDB RDS for MySQL instance.

G

  • RDS High-availability Edition

    In RDS High-availability Edition, a secondary RDS instance is provided as a standby for the primary RDS instance. Data is replicated from the primary RDS instance to the secondary RDS instance in semi-synchronous mode. If the primary RDS instance becomes faulty, your database system performs a failover to the secondary RDS instance.

    For more information, see RDS High-availability Edition.

H

  • recycle bin

    Some RDS instances are moved to the recycle bin after they expire or are released. You can unlock, rebuild, or destroy the RDS instances in the recycle bin.

    For more information, see Manage instances in the recycle bin.

I

  • I/O

    The read and write operations that are performed on a disk.

  • IOPS

    IOPS indicates the number of read and write operations that are performed to read and write 4 KB of data on a block storage device per second.

  • IP address whitelist

    An IP address whitelist of an RDS instance consists of the IP addresses and CIDR blocks that are granted access to the RDS instance. The IP address whitelists that you configure for an RDS instance are used to control access to the RDS instance. We recommend that you update the configured IP address whitelists on a regular basis.

    For more information, see Use a database client or the CLI to connect to an ApsaraDB RDS for MySQL instance.

J

  • JDBC

    Java Database Connectivity (JDBC) is a Java-based API that is used to connect to an RDS instance from a database client.

  • schema migration

    DTS can be used to migrate the schemas of objects to a destination instance.

  • classic network

    RDS instances in the classic network cannot be isolated by using network settings. You can block unauthorized access to the RDS instances in the classic network only by configuring IP address whitelists or security groups.

  • RDS Cluster Edition

    RDS Cluster Edition is supported only for RDS instances that run SQL Server 2017. RDS Cluster Edition is developed based on the native SQL Server technology Always On. In RDS Cluster Edition, computing is separated from storage, and you can create read-only RDS instances to implement read/write splitting. After you create read-only RDS instances, you can apply for a read-only routing endpoint, which is used to implement read/write splitting. By default, an independent internal endpoint is assigned to each read-only RDS instance. This internal endpoint is used to connect only to the read-only RDS instance to isolate queries.

    RDS Cluster Edition for ApsaraDB RDS for MySQL uses a high availability (HA) architecture that contains one primary node and multiple secondary nodes and supports compute-storage separation. RDS Cluster Edition provides the following features: automated failover, primary/secondary switchover, readable secondary nodes, node addition and deletion, multi-zone disaster recovery, node-level monitoring, and cluster topology management. RDS Cluster Edition also allows you to use the MySQL group replication (MGR) mode to ensure a recovery point objective (RPO) of 0. An RDS cluster is more cost-effective, flexible, and reliable than a self-managed database.

    For more information, see RDS Cluster Edition.

  • RDS Basic Edition

    RDS Basic Edition is cost-effective. In this edition, your database system consists of only one primary RDS instance, and computing is separated from storage.

    For more information, see RDS Basic Edition.

K

  • zone

    A zone is a physical location that is provided with independent power supply and networks in a region. All zones in a region provide similar services.

L

  • connections

    Connections indicate the number of connections that are established over TCP between a database client and an RDS instance. If a connection pool is enabled on the database client, the connections between the database client and the RDS instance are long-lived. Unlike short-lived connections, long-lived connections are not actively closed after the read and write requests over the connections are processed.

    For more information, see Configure the connection pooling feature.

  • logical I/O

    The read and write operations that are performed by an application on a file system.

M

  • MaxCompute

    MaxCompute, previously known as ODPS, is a fully managed computing platform that can process terabytes or petabytes of data at high speeds. MaxCompute supports comprehensive data import solutions and various classic distributed computing models. These solutions and models are used to import large amounts of data from RDS instances into MaxCompute. You can process the data by using MaxCompute.

    For more information, see What is MaxCompute?

  • Microsoft AD

    Active Directory (AD) is a directory service that is developed by Microsoft for various Microsoft services, such as Windows Standard Server, Windows Enterprise Server, and Microsoft SQL Server. A directory is a hierarchical structure that stores information about the objects on the same LAN. For example, AD stores information about user accounts, such as names, passwords, and phone numbers, and allows other authorized users on the same LAN to access the information.

    AD is an important part of the Windows ecosystem. A large number of large-sized enterprises use the domain control mechanism that is provided in the Windows ecosystem to plan and implement centralized access management in their business scenarios.

  • MongoDB

    ApsaraDB for MongoDB is a stable, reliable, and scalable database service that is fully compatible with the MongoDB protocol. You can store structured data in ApsaraDB RDS and unstructured data in ApsaraDB for MongoDB to meet various storage requirements.

    For more information, see What is ApsaraDB for MongoDB?

  • slow SQL statement

    If an SQL statement requires a long period of time to run, the SQL statement is a slow SQL statement.

    For more information, see Use the slow query log analysis feature.

O

  • OSS

    Object Storage Service (OSS) is a secure, cost-effective, and high-durability cloud storage service that is provided by Alibaba Cloud. You can use OSS to store large amounts of data in the cloud.

    For more information, see What is OSS?

  • OpenAPI

    ApsaraDB RDS provides an API for third-party developers.

    For more information, see List of operations by function.

Q

  • QPS

    Queries per second (QPS) indicate the number of SQL statements that are executed on an RDS instance per second. These SQL statements include INSERT, SELECT, UPDATE, DETELE, and COMMIT.

  • synchronous mode

    After an update operation originated from an application is complete on a primary RDS instance, the update log record is synchronized to all secondary RDS instances of the primary RDS instance. The update transaction is considered committed after at least one of the secondary RDS instances receives the update log record. The synchronous mode cannot degrade to the asynchronous mode. The synchronous mode is supported only for RDS Enterprise Edition. In addition, if you use RDS Enterprise Edition, the data replication mode cannot be changed.

  • full data migration

    DTS can migrate the data of all objects from the source RDS instance to a destination RDS instance.

R

  • RAM

    Resource Access Management (RAM) is a service that is provided by Alibaba Cloud to manage user identities and resource access permissions. You can grant the permissions on specific RDS instances to RAM users.

    For more information, see What is RAM?

  • RDS

    ApsaraDB Relational Database Service (RDS) is a stable, reliable, and scalable online database service that is built on top of the Apsara Distributed File System and high-performance SSDs of Alibaba Cloud. ApsaraDB RDS supports the MySQL, SQL Server, PostgreSQL, and MariaDB database engines. ApsaraDB RDS provides a complete suite of solutions for various scenarios, such as disaster recovery, backup, restoration, monitoring, and migration, to facilitate database O&M.

    For more information, see What is ApsaraDB RDS?

  • Redis

    ApsaraDB for Redis is a database service that provides a hybrid of memory and hard disks to ensure data persistence. You can use ECS, ApsaraDB RDS, and ApsaraDB for Redis together to handle a large number of read requests within a short period of time.

    For more information, see What is ApsaraDB for Redis?

S

  • standard SSD

    In ApsaraDB RDS, cloud disks consist of standard SSDs and ESSDs. A standard SSD is an elastic block storage device that is designed based on a distributed storage architecture. You can store data on standard SSDs to separate computing from storage.

    For more information, see Storage types.

  • SSL

    Secure Sockets Layer (SSL) is developed by Netscape to establish encrypted connections between web servers and browsers. SSL supports various encryption algorithms, such as RC4, MD5, and RSA. The Internet Engineering Task Force (IETF) upgraded SSL 3.0 to TLS. ApsaraDB RDS supports SSL for the MySQL, SQL Server, and PostgreSQL database engines. ApsaraDB RDS provides a server SSL certificate for each RDS instance. You can use the server SSL certificate of your RDS instance to determine whether the database service that you access by using a specific IP address and a specific port number is provided by your RDS instance. This can help defend against man-in-the-middle attacks. ApsaraDB RDS also allows you to enable and update the server SSL certificate for your RDS instance to ensure the security and validity of each server SSL certificate.

    For more information, see Configure the SSL encryption feature.

  • SSMS

    SQL Server Management Studio (SSMS) is an integrated environment that is used to manage SQL infrastructure. You can use SSMS to configure, monitor, and manage database instances that run SQL Server. In addition, SSMS provides various tools that can generate queries and scripts to deploy, monitor, and upgrade the components at the data layer. These components include the databases and data warehouses that run on applications.

  • RDS instance

    An RDS instance is a database process that exclusively occupies the allocated memory resources on a physical host. An RDS instance can be considered a virtual database server. You can specify different memory sizes, storage capacities, and database engines for different RDS instances. You can create and manage multiple databases on an RDS instance.

  • database

    A database is a logical unit of an RDS instance. It is a set of data that is stored with minimal redundancy in an organized manner. The data in databases is independent of the data on applications. The data can be shared among multiple authorized users. A database can be considered a data warehouse that is used to store data. You can create multiple databases on an RDS instance. Each database must have a unique name in the RDS instance on which the database is created.

  • database proxy

    A dedicated proxy resides between a database system and an application. The dedicated proxy receives requests from the application and routes the requests to the primary and read-only RDS instances in the database system. The dedicated proxy is easy to use and maintain, and provides high availability and high performance. The dedicated proxy also provides advanced features, such as automatic read/write splitting, transaction splitting, and connection pools.

    For more information, see What are database proxies?

  • deadlock

    When you run a transaction to modify specific resources, the resources are locked to prevent other concurrent transactions from modifying the resources and ensure data consistency. This lock is known as a deadlock. In most cases, deadlocks are triggered if multiple transactions are run to modify the same resources.

  • sequential I/O

    Sequential I/O indicates the contiguous read and write operations that are sequentially performed on a disk.

  • random I/O

    Random I/O indicates the read and write operations that are performed on a disk at random.

  • RDS Enterprise Edition

    RDS Enterprise Edition is suitable for enterprises. In this edition, your database system consists of one primary RDS instance, one secondary RDS instance, and one logger RDS instance. Data can be synchronized from the primary RDS instance to the secondary RDS instance and the logger RDS instance in synchronous mode, ensuring strong data consistency and finance-grade reliability.

    For more information, see RDS Enterprise Edition.

T

  • TDE

    ApsaraDB RDS supports transparent data encryption (TDE) for the MySQL and SQL Server database engines. TDE is used to instantly encrypt and decrypt the data files that are read from and written to an RDS instance. Data is encrypted before it is written to a disk and is decrypted when it is read from a disk to the memory. After TDE is enabled for your RDS instance, the size of data files in the RDS instance does not increase. You can use TDE without the need to modify the configurations of your application.

    For more information, see Configure TDE.

  • TPM

    Transactions per minute (TPM) indicates the number of transactions that are run on an RDS instance per minute.

  • TPS

    Transactions per second (TPS) indicates the number of transactions that are committed on an RDS instance per second.

V

  • VPC

    A virtual private cloud (VPC) is an isolated network that provides higher security and higher performance than the classic network.

    For more information, see What is a VPC?

W

  • physical I/O

    Physical I/O indicates the read and write operations that are initiated by a file system to a disk.

X

  • performance insight

    Performance insight is a feature of DAS. This feature provides instance-level load monitoring, association analysis, and performance optimization. This feature helps you evaluate the loads on an RDS instance and troubleshoot performance issues to increase the stability of the RDS instance.

Y

  • asynchronous mode

    After an add, delete, or modify operation that is initiated by your application is complete on the primary RDS instance, the primary RDS instance immediately responds to the application. At the same time, the primary RDS instance replicates the added, deleted, or modified data to the secondary RDS instance. In asynchronous mode, the unavailability of the secondary instances does not interrupt the workloads on the primary instance. However, the unavailability of the primary instance may cause data inconsistencies between the primary and secondary instances.

  • disaster recovery RDS instance

    If your primary RDS instance is used for business scenarios in which high data reliability or compliance with financial regulations is required, you can create a disaster recovery RDS instance that runs MySQL to increase data reliability. The disaster recovery RDS instance synchronizes data from the primary RDS instance in real time by using DTS. The primary RDS instance and the disaster recovery RDS instance are configured as a high-availability architecture. If the primary RDS instance and the secondary RDS instance are inaccessible due to unexpected exceptions such as natural disasters, the database system fails over to the disaster recovery RDS instance. In this case, the disaster recovery RDS instance is promoted to run as the new primary RDS instance. After you update the endpoint information on the application that is connected to the database system, the application immediately connects to the new primary RDS instance.

    For more information, see Create a disaster recovery ApsaraDB RDS for MySQL instance.

  • emergency RDS instance

    DBS provides an emergency recovery feature. This feature allows DBS to obtain the data backup files of an RDS instance and generate snapshots. Then, DBS can produce an emergency RDS instance in a few dozen seconds. The emergency RDS instance is also known as a DBS sandbox instance.

    For more information, see Use the emergency recovery feature.

Z

  • read-only RDS instance

    If a database system processes a large number of read requests from an application, you can create read-only RDS instances that are used to offload read requests from the primary RDS instance of the database system. This increases the read capability of the database system and the throughput of the application.

    For more information, see Overview of read-only ApsaraDB RDS for MySQL instances.

  • read-only QPS

    The number of SELECT statements executed per second when read-only operations are performed on the database.

  • incremental data migration

    After full data migration is complete, DTS synchronizes incremental data from the source RDS instance to the destination RDS instance. Incremental data migration allows you to ensure service continuity when you migrate data between RDS instances.

  • character set

    A character set is a collection of letters, symbols, and rules that are used to encode the letters and symbols in a database.