Examinations
Exam registration address: https://www.oceanbase.com/training/detail?level=OBCA
After registering for the exam, everyone in the session will be pulled into a DingTalk group, where OB teachers will provide relevant guidance. The exam time can be adjusted by contacting the teacher;
Use DingTalk to take the exam online, either using a computer or a mobile phone;
The staff will start the video before the exam starts, and it needs to be kept on during the process. You can hang up directly after handing in the exam;
After exiting midway, you can re-enter before the end of the exam;
Before the exam, you must select the right organization on DingTalk, which should be "OceanBase Exam Certification". In addition, the entrance will not be opened before the exam starts, and there will be a reminder 5-10 minutes before the exam.
Examination rules
The full score is 100 points, and the passing score is 60;
Question type: single choice/multiple choice/judgment, 50 questions in the test paper;
learning method:
You can go through all the video content, which is more comprehensive. Combined with online documents and trial product packages, you can achieve comprehensive learning;
The official certification training study materials are also worth reading. There are exam questions at the end of each chapter;
Some question banks on the Internet are all original examination questions, so you need to collect more and read more;
References
OBCA官方线上学习视频：https://www.oceanbase.com/training/detail?level=OBCA
You can download the PPT used in the online class here
Some collected question banks
OceanBase OBCA exam summary (key points + question bank)
Judgment:
- A tenant can have one or more resource unit UNIT pairs on the same server.
- When creating a resource unit, you only need to specify the CPU and MEMORY parameters. There is no need to specify OPS, DISK_SIZE, and SESSION_NUM. Parameter errors
- OCEANBASE can achieve RPO=0 and RTO<30 seconds correctly when a few replicas are unavailable.
- Zone can correspond to different cities, or different computer rooms in a city, or different racks in a computer room to achieve different levels of disaster recovery accuracy.
- The primary copy can only be dispersed into all Zones to achieve load balancing of access traffic. The primary copy cannot be focused into one Zone; Error
- OceanBase has been released to Alibaba Cloud public cloud and private cloud correctly
- After the expansion server joins the cluster, the cluster will migrate the primary copy and slave copy to the expansion server based on the load balancing strategy to achieve correct overall load balancing.
- Tenants are logically similar to traditional database instances. After creation, each tenant has its own dedicated process.
- OceanBase's Paxos protocol is different from traditional primary and secondary databases or dual-selection solutions, and can completely avoid the split-brain problem in disaster recovery scenarios (that is, the scenario of two primary databases at the same time) Correct
- TCP-C is a benchmark test. There are no official rules. As long as you can achieve a high score, it’s fine.
- Each OB Server is relatively independent and has its own independent SQL engine. If the data required by the application is not on the current OB Server, the OB Server will coordinate the data of other OB Servers and uniformly feed back to the application. This process is very important for the application. . correct
- Modifying the resource pool can realize another way to expand/reduce the tenant's capacity, such as increasing/decreasing the number of nodes in each zone, which can be achieved correctly by modifying the unit_num of the resource pool;
- When creating a tenant, you need to specify the tenant type as Oracle tenant or MYSQL tenant to meet the needs of different developers. correct
- The same resource unit definition unit cofig (such as 2C8G, or 4C16G, etc.) can be used by multiple resource pools. Error multiple choice:
- The OMS real-time synchronization tool is a powerful tool for migrating heterogeneous databases to OceanBase. What functions does OMS support: BCDE A: Supports session management and visual modification of system global variables. It is difficult for users to memorize variables. B: Supports multiple types of data sources, including Oracle
. , MYSQL, DB2, OceanBase and other databases to OceanBase full migration and incremental real-time data synchronization
C: One-stop interaction, full life cycle management of data migration, the creation, configuration and monitoring of data migration are all completed in a continuous operation on the management and control interface. Easy interaction D: Compatibility assessment and transformation:
OceanBase's object compatibility assessment and rewriting suggestions for heterogeneous data migration greatly reduce the threshold of business migration and the difficulty of business transformation.
E: Multiple data verification: Provides protection through multiple verification methods. It is necessary to ensure data quality in a more comprehensive, time-saving and funny way; at the same time. .- Regarding the Zone of OceanBase, the following statement is correct: CDEF A: Each Zone can contain multiple copies of a partition B: Different Zones must be deployed in different computer rooms C: Multiple copies of a partition should be distributed in different Zones , each Zone has and only one fully functional copy of the partition.
D: Available Zone means available zone, usually refers to a computer room. E: An OceanBase cluster is composed of several Zones. F: A
Zone includes several physical servers.- What applications does Ocean currently have: ABCD
- Regarding the effective range of OceanBase system parameters, the following statement is correct: ABC A: It can take effect on a certain OBServer B: It can take effect on a certain Zone C: It can take effect on the cluster range D: It can take effect on a certain Region
- As the business continues to develop, the resources of the original tenants cannot meet the business needs. What are the expansion methods? BC A: The tenant cannot be expanded and a new tenant needs to be created to meet business needs. B: Adjust the number of resource units in the resource pool. If the original number is 1, it can be increased to 2. C: Adjust the number of resource units in the resource pool. Resource unit
rules, for example, the previous specification was 2C8G, which can be adjusted to 4C16G- RootService master control service provides resource allocation and scheduling functions, which mainly include: ABCD A: Partition and copy management B: Dynamic load balancing C: SQL engine D: Expansion and reduction
- Regarding the OceanBase modification system parameter command ALTER SYSTEM SET XX='YY', the following statements are correct: ABCE A: If no conditions are required, an error will be returned; B: The value of the Parameter in a certain zone can be modified C:
The value of the Parameter on a specific OBServer can be modified. D: Without any conditions, the values of all OBServers can be modified. E:
The value of the Parameter on a certain Region can be modified.- Regarding the partitioning of OceanBase, the following statement is correct: AB A: The data table is split into multiple partitions according to the partition rules. Each partition includes several row records in the table. B: Each partition can also use different partitions. Dimensions are then partitioned, called secondary partitions.
C: OceanBase only supports first-level partitions and does not support secondary partitions. D: OceanBase partitions are the smallest unit for data migration and the smallest unit for high-availability switching. E: OceanBase
supports automatic partitioning of tables. Split- Regarding the tenant expansion method, the following statement is correct: AB A: To expand the tenant, you can first complete the cluster expansion by adding service nodes, and then complete the tenant expansion by increasing the number of resource units. B: If the cluster and node resources are sufficient, you can Directly modify the resource unit specifications related to the tenant resource pool for expansion C: OceanBase
is a distributed cluster with the ability to expand horizontally. Tenant expansion only requires adding stages, and there is no need to expand the tenant's resource unit. D
: The tenant cannot expand if Resources cannot meet demand, and tenants with a larger resource pool need to be re-established.- System administrators can create different tenants according to business needs. What are the characteristics of tenants ABCD A: Have their own independent system variables B: Have independent system databases such as information_schema C: Can create their own users D: Can create databases, tables, etc. object
1. Multiple choice question
Score: 2
When using JDBC to connect to Oracle tenants, which JDBC driver is needed? C
A. MySQL standard JDBC driver
B. Oracle standard JDBC driver
C. Ocean Base’s own JDBC driver
D. No Need to drive2. Multiple-choice question score: 2.5 What benefits can Ocean Base’s “quasi-memory database” + LSM Tree architecture bring? ABCD A.
In order to avoid data loss in memory, redo-log uses the WAL mechanism to write to the disk in real time to ensure Data persistence;
B. Quasi-memory processing, data modification is mainly memory operations, without frequent checkpoint operations, improving write performance; C.
After the dirty data in the memory is merged in batches, it is sequentially written to the SSD hard disk to avoid random writes, improve write performance and Extend the life of SSD;
D. Disk data is arranged in an orderly manner according to primary keys, with less disk fragmentation and fast retrieval capabilities. Use ordinary read-intensive SSD hard drives;
3. Multiple choice question score: 2.5
What are the two levels of OceanBase parameters? BD
A, Zone level B, Tenant level C, OBServer level D, Cluster level11. Single-choice question score: 2
When an application writes data to the database, it will access the master copy by default. This time, the master copy will be
synchronized () to the slave copy to ensure high availability of data. B
A. Undo-log
B. Redo-Log
C. System log
D. Heartbeat message
12. Single-choice question
Points: 2
Ocean Base forms a Paxos protocol group in units of (). D
A. Tenant
B, table
C, database
D, partition
13. Multiple choice question score: 2
Ocean Base cluster can support both MySQL and Oracle tenants. Which black screen tool can connect to Oracle tenants? C A.
ODC Developer Center
B. OCP management platform
C. Ocean Base client
D. Standard MySQL client
14. Single-choice question score: 2
Which command can be used to query the properties of parameters? B
A. show variables like'%%';
B. show parameters like'%%';
C. set@@global.=;
D. alter system set=;
15. True or False question score: 1
The administrator needs to manually specify which copy of a partition is the master copy and which is the slave copy. FError
Correct
_
16. Multiple-choice question score: 2.5
OMS real-time synchronization tool is a powerful tool for migrating heterogeneous databases to Ocean Base database. What functions does OMS support? ABC A. Compatibility assessment and transformation: Object compatibility assessment
of heterogeneous data migration Ocean Base
and rewriting suggestions, greatly reducing the threshold for business migration
and the difficulty of business transformation.
B. Supports multiple types of data sources: supports full migration and incremental real-time data synchronization from
databases including Oracle, MySQL, DB 2, Ocean Base, etc. to Ocean Base . C. Multiple data verification: Provides protection from multiple verification methods to ensure data quality in a more comprehensive, time-saving and efficient manner; at the same time, it displays differential data and provides a quick way to make corrections. D. Supports visual modification of session variables and system global variables, reducing the difficulty for users to memorize variables. 17. Single-choice question score: 2 Ocean Base is a cluster. Which of the following components manages the entire cluster and supports functions such as global DDL and cluster data merging? . B A. ODC Developer Center B. Root Service Master Control Service C. OB Proxy D. OCP Management Platform 18. True or False Question Score: 1 The same resource unit defines unit config (such as 2C8G, or 4C16G, etc.), which can be used by multiple resource pool to use. T Correct Wrong 19. True or False question score: 1 Once the tenant's resource pool is created, it cannot be changed. F
Wrong
Correct
20. Single-choice question score: 2
Regarding the consistency characteristics of the Ocean Base transaction engine, what is the correct description? A A. Consistency
constraints such as ensuring the uniqueness of the primary key
B. Consistency constraints such as not guaranteeing the uniqueness of the primary key
C. Mandatory requirements for all Column uniqueness constraint
D. Forced removal of non-primary key uniqueness constraints
21. Single-choice question score: 2
After the tenant is created, you can use the black screen client to connect to the database, in addition to specifying the IP, port number, user name, password, etc. of the database In addition to the information, what form of connection does Ocean Base generally use? C
A. Database name@user name, such as ocean base@root
B. Tenant name@user name, such as sys@root
C. User name@tenant name, such as root@sys
D , Username@database name, for example root@ocean base
22. True or False question score: 1
Zone can correspond to different cities, or different computer rooms in a city, or
different racks in a computer room. T
Wrong Correct
23.
Single-choice question score: 2
Which of the following components provides a graphical management interface and supports cluster management, tenant management, monitoring and alarming and other functions? B A
, OB Proxy
B, OCP cloud management platform
C, OBServer
D. ODC Developer Center
24. Multiple choice question score: 2.5
Regarding the ALTER SYSTEM SET command to modify the system parameters of Ocean Base, which of the following statements is correct? ADE
A. The value of the Parameter on a specific OBServer can be modified.
B. If there are no conditions, an error will be returned.
C. It can be modified. The value of the Parameter in a certain Region
D. If there are no conditions, the value of all OBServers will be modified. Oc earb19
E. The value of the Parameter in a certain Zone can be modified.
25. Judgment question score: 1
Global level (tenant Level) After the variable is modified, it will still be effective for the currently opened session. F
Wrong
Correct
26. True or False question score: 1
memory_limit_percentage is set to 90, which means that memory writing to 90% will trigger a merge operation. F
Wrong
Correct
27. Single-choice question score: 2
In order to achieve better compression effects, Ocean Base will generally perform several compressions. C
A, 4 times
B, 3 times
C, 2 times
D, 1 time
28. Multiple choice question score: 2.5
What client tools does Ocean Base support? ABCD
A. White screen tool-OCP management platform
B. Black screen tool-Ocean Base client
C, black screen tool-standard MySQL client
D, white screen tool-ODC Developer Center
29. Single-choice question score: 2
Which technology does Ocean Base use to solve the problem of read and write mutual exclusion? B
A. Global snapshot
B, MVCC
C. Paxos protocol
D. Mutex lock
30. Multiple-choice question score: 2.5
Tenants are similar to instances of traditional databases. Administrators can create tenants according to business needs. What characteristics does tenants have? ABCD
A. Can create all subject objects such as databases and tables.
B. Has its own independent system variables
. C. Can create its own users.
D , have independent information_schema and other system databases
31. Score for judgment question: 1
Zone is a logical concept, which is to give a batch of machines in the cluster the same tag, and servers belonging to the same tag belong to a Zone. T
Wrong Correct
32.
Multiple-choice question score: 2.5
A partition generally has multiple copies. What types of replicas does Ocean Base support? ACD
A, all-purpose type
B, write-only type
C, read-only type
D, log type
33. True or False question score: 1
Each OBServer is relatively independent and has its own independent SQL engine. , if the data required by the application is not on the current OBServer, the OBServer will coordinate the data of other OBServers and uniformly feed it back to the application. This process is transparent to the application. T
Wrong Correct 34. True or False question score:
1
TPC-C is a benchmark test, there are no rules and regulations, as long as you can achieve high scores. F
Correct
Wrong
35. Single-choice question score: 2
The Alter system command can modify cluster parameters and tenant parameters. For example, this command specifies Zone or OBServer. How many Zones or OBServers can be specified at most at the same time? A A
, 1
B, 3
C. 2
36. Multiple-choice question score: 2.5
Regarding the tenant rights management of Ocean Base, which of the following statements is correct? BCD
A. Administrator users under the system tenant can access the user data of other ordinary tenants
B. Only the system tenant Only administrator users under the system tenant have cluster management rights and can perform system management operations, such as creating/deleting ordinary tenants, setting system configuration parameters, and enabling daily merge operations. C. Administrator users
under the system tenant can perform operations for users of other ordinary tenants. Authorization allows users of ordinary tenants to have system administrator permissions
D. Users under any tenant (whether system tenant or ordinary tenant) cannot access user data under other ordinary tenants across tenants
37. Multiple-choice question score: 2.5
About OCP monitoring function, which of the following statements is correct? ABCDE
A. You can customize monitoring items
B. You can monitor the overall performance of the cluster
C. You can monitor the entire disk
D. You can turn off the monitoring of a certain cluster or tenant
E. You can monitor performance trends
38 , True or False question score: 1
Ordinary tenants cannot change their own system variables, and need system tenants (sys) to change the configuration items of other ordinary tenants. F
is correct
Error
39. Multiple-choice question score: 2.5
Regarding the MVCC (Multiple Version Concurrency Control) of the Ocean Base transaction engine, which of the following statements is correct? ABC
A. The read operation reads the committed data of a specific snapshot version
B. All modified rows Add a mutex lock to achieve write-write mutual exclusion
C. Reading and writing do not block each other
D. Writing blocks reading operations
40. Single-choice question score: 2
What is the database kernel used in the Ocean Base product? A
A. Completely autonomous R&
D B, MySQL
C, PostgreSQL
D, H base
41. Single-choice question score: 2
What is the election protocol used by the Ocean Base core? B
A. Raft
B, Paxos
C, ZAB
D, Zookeeper
42. Multiple-choice question score: 2.5
Are the following descriptions about Ocean Base passing TPC-C certification correct? AC
A. Ocean Base passed TPC-C certification using Alibaba Cloud public cloud environment
B. Ocean Base is the first domestic database to pass certification
C. Ocean Base is the world's first certified distributed database
D. Ocean Base has only undergone TPC-C certification once
43. Multiple-choice question score: 2.5
What data does the Ocean Base backup and recovery function support backup and recovery? ABCDE
A. System variables
B. View information
C. User information
D. Table definition
E. User permissions
44. Single-choice question score: 2
mini freeze is a simple dump operation. The data of multiple mini freezes will be () merged; multiple minor freezes will () merge, but will not merge with S STable. A
A. Asynchronous, real-time
B. Discrete, real-time
C. Real-time, discrete
D. Real-time, asynchronous
45. Multiple-choice question score: 2.5
What transaction isolation levels does Ocean Base support? AD
A. Read-Committed
B. Repeatable-Read
C , dirty read
D. Serializable
46. Single-choice question score: 2
Which command does the administrator use to create a resource pool? B
A. create resource unit
B. create resource pool
C. create database
D. create tea nant
47. Single-choice question Score: 2
What operating system does Ocean Base not support? C
A, Winning Kirin
B, CentOS
C, Windows
D, Galaxy Kirin
48, Multiple choice question score: 2.5
What storage media does the Ocean Base backup and recovery service support? AB
A, NFS
B, Alibaba Cloud OSS
C, IP-SAN
D, FC-SAN
49. Multiple-choice question score: 2.5
When the server where the primary copy is located has a hardware failure or a network failure, the business will How does Ocean Base ensure high availability when the data of the primary replica cannot be accessed normally? AD
A. The primary replica cannot contact all the slave replicas. It becomes a minority and will automatically step down as the primary replica.
B. The administrator needs to manually find the remaining slave copies and manually convert them from slave copies to master copies.
C. The master copy cannot contact all slave copies, and it is still the master copy, causing "brain gap" between the two master copies. D.
The remaining slave replicas still form a majority, and a new master replica is automatically selected to take over the business. The switching process is invisible to the business. 50. Multiple-choice question
score: 2.5
Regarding the tenant expansion method, which of the following statements is correct? ? AC
A. If the cluster and node resources are sufficient, you can directly modify the resource unit specifications related to the tenant resource pool to expand the capacity. B. The
tenant cannot expand the capacity. If the resources cannot meet the demand, you need to re-establish a tenant with a larger resource pool.
C. Ocean Base is a distributed cluster with the ability to expand horizontally. Tenant expansion only requires adding nodes. There is no need to expand the tenant's resource unit. D.
Tenant expansion can complete the cluster expansion by adding nodes, and then expand the tenant's resource unit
51 . True or False question score: 1
When creating a tenant, you need to specify the tenant type as Oracle tenant or MySQL tenant. Once specified, it is difficult to change later. T Wrong
Correct 52. Multiple choice question score: 2
When a cluster failure occurs (server failure or network failure), what is the granularity of Ocean Base failover? A
A. Table or sub-partition of the partition table
B. Database
C. Tenant
D. Cluster
53. Single-choice question score: 2
If a cluster has 3 zones, each zone has 5 OBServers. The Unit eNum of the resource pool corresponding to a tenant is 4. How many servers in the cluster have the resource module of the tenant? D A, 3 B, 15 C, 5 D
,
12
Multiple
choice
question score: 2
Ocean Base What type of database is it? D
A: No SQL database
B: Centralized database
C: Graph database
D: Distributed relational database
2. Single-choice question score: 2
When the cluster fails (server failure or network failure) , What is the granularity of Ocean Base failover? D
A: Database
B: Tenant
C: Table or sub-partition of a partition table
D: Cluster
3. Single-choice question score: 2
Assume that the Ocean Base cluster has 3 Zones, 2 of which Zone is deployed in two computer rooms in one city, and the other Zone is deployed in a computer room in another city. If a computer room in the same city goes down, which of the following statements is correct? C
A: The upper-layer business side will be affected
B: The strong consistent synchronization delay will remain unchanged
C: The remote synchronization delay will be increased
D: Second-level data will be lost
4. Single-choice question score: 2
Which of the following descriptions is not a feature of the Ocean Base architecture? B
A: Full peer node
B: Central control
C: Quasi-memory database D
: Multiple copies
5. Single-choice question Score: 2
Which of the following descriptions about Ocean Base expansion and contraction is correct? D A
: Public cloud resources cannot be used
B: Certain business modifications are required
C: Administrators are required to suspend the business
D: Dynamic expansion and shrinkage are supported. Upper-layer business transparency
6. Single-choice question score: 2
Alter system command can modify cluster parameters and tenant parameters. For example, this command specifies Zone or OBServer. How many Zones or OBServers can be specified at most at the same time? B A: 3 B
:
1
C: 4
D: 2
7. Single-choice question score: 2
Regarding Ocean Base resource isolation, which of the following statements is correct? C A
: Ocean Base uses server isolation
B: Ocean Base uses database isolation
C: Ocean Base uses tenants Isolation
D: Ocean Base uses schema isolation
8. Single-choice question score: 2
What is the database kernel used in Ocean Base products? C
A: PostgreSQL
B: H base
c: Completely independent research and development
D: MySQL
9. Single-choice question score: 2
Regarding the Root Service master control service, which of the following descriptions is correct? A A
: Generally, one is deployed in each Zone, co-located with an OBServer in the Zone, and shared One server
B: Each OBServer needs to deploy Root Service master control service to provide higher availability
C: It is enough to deploy one Root Service master control service for the entire cluster, and there is no need to consider high availability
D: Generally, each Zone is deployed One, an independent server must be used to run the Root Service service, which cannot be co-located with OBServer.
10. Single-choice question score: 2
By configuring Pri may Zone, you can break the load balance and aggregate the primary replicas into a Zone. Which level does Ocean Base not support? D
◎A: Database level. When creating a database, you can set Primary Zone
B: tenant level. When creating a tenant, you can set the Primary Zone.
OC: cluster level. When creating a cluster, you can set the Primary Zone,
OD: table level. When creating a table, you can set the Primary Zone.
11. Single-choice question score: 2
What is the storage structure of Ocean Base? B
A: Cache database
B: Quasi-memory database
C: Hard disk database
13. Single-choice question score: 2
Ocean Base is a cluster. Which of the following components manages the entire cluster resources and supports functions such as global DDL and cluster data merging D
A: ODC Developer Center
B: OB Proxy
C: OCP Management Platform
D: Root Service Master Control Service
14. Multiple choice question score: 2
Ocean Base integrates incremental data and baseline data to generate a new baseline. This process is called Why? C
A: Freeze
B: Compress
C: Merge
D: Dump
15. Single-choice question score: 2
What operating system does Ocean Base not support? B
A: Galaxy Kirin
B: Windows
OC: CentOS
D: Winning Kirin
16 , Single-choice question score: 2.
For the existing Oracle business to be migrated to Ocean Base, real-time data synchronization function is required. Which tool is recommended? B A
: OCP
B: OMS
C: ODC
D: Data X
17. Single-choice question score :2Which
of the following components provides a graphical management interface and supports cluster management, tenant management, monitoring and alarm functions? A A
: OCP cloud management platform
B: ODC Developer Center
C: OBServer
D: OB Proxy
18. Single-choice question points Value: 2
What does it mean when "major_freeze_duty_time" is set to "02:00"? B
A: Every day at 2 a.m., the system automatically initiates a dump operation.
B: Every day at 2 a.m., the system automatically initiates a memory freeze operation. C: Every day at 2 a.m., the system automatically initiates a backup and recovery operation . D: Every day at 2 a.m.,
the system automatically initiates a backup and recovery operation.
At 2 o'clock, the system automatically initiates a merge operation
19. Single-choice question score: 2
What is the election protocol used by the Ocean Base core? A A
: Paxos
B: Raft
OC: ZAB
OD: Zookeeper
20. Single-choice question score:
2 When an application writes data to the database, it will access the master copy by default. This time, the master copy will be synchronized () to the slave copy to ensure high availability of data. D
A: Heartbeat message
B: System log
C: Undo-log
D: Redo-Log
21. Multiple-choice question score: 2.5
A partition generally has multiple copies. What types of copies does Ocean Base support? ABC
A: Log type
B: Read-only type
C: All-purpose type
D: Write-only type
22. What are the applications of Ocean Base within Alibaba and Ant Group? BCD
A: India Pay tm
B: Taobao Favorites
C: Online Banking
D: Alipay
23. Multiple choice question score: 2.5
Which of the following descriptions of OB Proxy is correct? AB
A: OB Proxy is located between the application and OBServer, routing application requests to the appropriate OBServer;
B: OB Proxy is a "stateless" service process and does not perform data persistence;
C: OB Proxy must be deployed on a computer On an independent server to ensure its performance requirements;
D: OB Proxy participates in the computing tasks and transaction processing of the database engine;
24. Multiple choice question score: 2.5
What are the core features of Ocean Base? ABDE
A: High scalability, can be used Ordinary PC servers are scaled vertically;
B: High performance, with a peak of 61 million times/second, and a maximum of 320 billion rows in a single table; C
: High cost, using proprietary hardware such as minicomputers and high-end storage;
D: High availability, ensuring strong consistency through Paxos protocol, RPO=0, RTO<30 seconds;
E: High compatibility, supporting MySQL and Oracle modes, reducing business migration and transformation costs;
25. Multiple-choice question score: 2.5 ABCD
Regarding the effective range of the system parameters of Ocean Base, which of the following statements is correct?
A: It can take effect in the cluster range
B: It can take effect in a certain Region
C: It can take effect in a certain Zone
D: It can take effect in a certain OBServer
26. Multiple Question score: 2.5 AD
Regarding the Ocean Base modification system parameter command ALTER SYSTEM SET XX='YY', which of the following statements is correct?
A: If without any conditions, an error will be returned
. B: If without any conditions, Then modify the values of all OBServers
C: The value of the Parameter in a certain Region can be modified.
D: The value of the Parameter in a specific OBServer can be modified.
F: The value of the Parameter in its Zone can be modified.
27. Multiple-choice question score: 2.5
What challenges does the traditional centralized relational database face? ABD
A: Lack of ecology: insufficient documentation, training, applications, etc.;
B: High cost: running on proprietary hardware such as high-end servers, minicomputers, and high-end storage;
C: Performance Poor: At any time, the performance of traditional centralized databases is worse than distributed databases;
D: Poor scalability: unable to get rid of the single-machine architecture and can only expand vertically, not horizontally;
28. Multiple-choice question score: 2.5
Ocean Base What are the two levels of parameters? BD
A: OBServer level
B: Cluster level
C: Zone level
D: Tenant level
29. Multiple-choice question score: 2.5
When the server where the primary copy is located has a hardware failure or a network failure, the business cannot normally access the primary. How does Ocean Base ensure high availability of replica data? BD
A: The master replica cannot contact all slave replicas, and it is still the master replica, causing a "split brain" phenomenon in which two master replicas exist at the same time. B: The remaining slave replicas are
still Form a majority and automatically select a new primary copy to take over the business. The switching process is invisible to the business.
C: The administrator needs to manually find the remaining slave copies and manually convert them from slave copies to the master copy.
D: The master copy cannot be contacted. to all slave copies, it becomes a minority and will automatically resign as the master copy
33. Multiple choice question score: 2.5
Regarding the application log level of Ocean Base, which of the following statements is correct? ADE
A: ERROR serious error, used to record system fault information, and troubleshooting must be performed, otherwise the system will be unavailable
B: WARN warning, used to record serious errors, Need to be processed immediately
C: INFO prompt, used to record the current status of system operation, this information is error message
D: WARN warning, used to record potential errors that may occur
E: INFO prompt, used to record the current status of system operation, This information is normal information
34. Multiple-choice question score: 2.5
What are the common reasons for failure to initialize the Ocean Base cluster (bootstrap)? BCD
A: OCP is not installed, causing the cluster bootstrap to fail.
B: When starting the OBServer process, the parameter information specified is: Error, such as an incorrect Zone name.
C: The clock error between machines is too large (more than 100 milliseconds). You can use nt pg, clock diff and other commands to check the clock differences between machines. D: The server hardware itself has a fault, such as a
storage fault.
35. Multiple-choice question score: 2.5
Ocean Base can achieve dynamic expansion and contraction. What steps does expansion include? BCD
A: The administrator manually starts the "rebalance" process and copies some data online from the Unit of the old server to the Unit of the new server. .
B: Execute the alter system add server; command for each newly added observer process to add the observer service to the cluster.
C: Execute the alter resource poolunit_num=; command to expand the number of units in the resource pool.
D: The expansion server correctly starts the OB service
36. Multiple-choice question score: 2.5
When a table is large, it can be split horizontally into several partitions. Each partition contains several rows of records in the table. What types of tables does Ocean Base support? Partitioning method? ABD
A: List partition (by list)
B: Range partition (by range)
C: Datetime partition
D: Hash partition
37. Multiple-choice question score: 2.5
Regarding the ZONE of Ocean Base, the correct statement below is ABCF
A : Zone means availability zone, usually referring to a computer room (data center, IDC)
B: An Ocean Base cluster, composed of several Zones
C: For data security and high availability, multiple copies of a partition are generally distributed On multiple Zones, each Zone has and has only one copy of the partition.
D: Each Zone can contain multiple copies of a partition.
E: Different Zones must be deployed in different computer rooms.
F: A Zone includes several physical servers.
38. Multiple-choice question score: 2.5
Regarding the MVCC (Multiple Version Concurrency Control) of the Ocean Base transaction engine, which of the following statements is correct? AB A:
Reading and writing do not block each other
B: The read operation reads the committed data of a specific snapshot version
C: Writing will block the read operation
D: Add mutex locks to all modified rows to achieve write-write mutual exclusion
39. True or False question score: 1
The copy of the partition only contains static data (S STable) on the hard disk, excluding Mem Table data and log data. F
Wrong Correct 40.
True or False question score: 1 0ceanBase database was incubated internally by Alibaba and Ant for 10 years before being gradually promoted to the external market. T Wrong Correct 41. True or False question score: 1 After the expansion server joins the cluster, the cluster will automatically migrate some of the master copies and slave copies to the expansion server based on the load balancing strategy to achieve overall load balancing. T Correct Wrong 42. True or False question score: 1 Under normal circumstances, each OBServer has a master copy and a slave copy to achieve overall load balancing and avoid uneven busyness and idleness of the OBServer. T Wrong Correct 43. True or False Question Score: 1 Each OBServer is relatively independent and has its own independent SQL engine. If the data required by the application is not on the current OBServer, the OBServer will coordinate the data of other OBServers and uniformly feed it back to the application , this process is transparent to the application. T Wrong Correct 44. True or False question score: 1 Tenants are logically similar to instances of traditional databases. After creation, each tenant will have its own dedicated process. F Misread Correct 45. True or False question score: 1 The data in Ocean Base are arranged in an orderly manner according to the primary key on the disk. T Wrong Correct 46. Score for true or false questions: 1
Ocean Base uses the Explain command to view the logical execution plan generated by the optimizer for a given SQL. The plan displayed by Explain is the logical execution plan generated by the optimizer based on the current user input and data statistics when executing the command, not when executing the command. The actual physical execution plan used in the plan level storage T
is wrong.
Correct
47. True or False question score: 1
Ocean Base can achieve RPO =O and R TO <30 seconds when a few copies are unavailable. T
Wrong Correct 48. True or False question score: 1
Ocean Base database is a reissued product based on an open source database. F Wrong Correct 49. True or False question score: 1 Ordinary tenants can only set the parameters of their own tenants. System tenants can view and set the parameters of all tenants (including system tenants and ordinary tenants). T Correct Wrong 50. True or False question score: 1 TPC-C is a running score test. There are no official rules and restrictions. As long as you can run a high score, F is correct . Wrong 51. True or False question score: 1 Modifying the resource pool can realize another way of expansion/maintenance of tenants. . For example, increasing/decreasing the number of nodes in each Zone can be achieved by modifying the unit_num of the resource pool. T Correct Wrong 52. True or False question score: 1 Zone is a logical concept, which is to assign the same tag to a batch of machines in the cluster. Servers belonging to the same tag belong to a Zone. T
Wrong Correct 53.
True or False question score: 1 When creating a user, you need to specify the user type as Oracle tenant or MySQL user to meet the needs of different developers. TCorrect Wrong _