First, test preparation materials
- Ticket printing: 1-2 weeks advance registration system logon ticket printing, in order to avoid the event, it is recommended to keep a ticket electronic files on the phone.
- Carry documents: ticket + ID card
- Carry pen ruler: pencil, black gel pen, ruler (title afternoon drawing).
- Exam time: morning (basic knowledge) 9: 00-11: 30 in the afternoon (Applied Technology) 2: 00-4: 30, in general, have to answer in order to carry out an assignment after 90 minutes.
- Answer purpose: the easier issues first.
Second, the chapters important test sites
"Computer system knowledge" important test center
- A controller configured and operator
- The original code, inverse code 0 indicates no unique, complement, shift of 0 indicates unique.
- Hamming code parity check bits: 2k≥n + k + 1
- Calculating character dot-matrix storage
- Instruction Set Category: CISC, RISC
- Pipelining: throughput, establish time lines
- Cache (Cache) and address mapping (direct mapping, fully associative, and set associative map image)
- Information Security 5 elements: (1) confidentiality, (2) integrity, (3) availability, (4) controllability, (5) auditability.
- Two types of data encryption: symmetric encryption (private key encryption) and asymmetric encryption (public key encryption).
- Reliability Model: Model series, parallel model.
- Attribute of the image: resolution (line resolution, the resolution of the column, the DPI unit), image depth
- Amount of image data (B) = Total depth image the image pixels × / 8
- Trichromatic principle: RGB color space, CMY color space, YUV color space
- Hypertext three basic elements: nodes, chains and networks
51 micro database systems engineer jobs
"2 program basics of the language" important test center
- Type four languages: imperative languages, functional languages, logic languages, target languages
- Static languages, dynamic languages
- Programming languages function parameter passing methods: call by value, call by reference, by name called, the macro expansion
- The basic process of compilation: lexical analysis, syntax analysis, semantic analysis and code generation, code optimization, object code generation, and the role of table management and error management, attention interpreted language does not generate object code.
- Chomsky (Chomsky) defines four categories of grammar and language
- NFA conversion to DFA's
- DFA Minimize: ① From eliminate excess state and dead state, ② combined equivalent states
- The regular expression or brake deduced which represents the sequence
- Intermediate code representation of: the syntax tree representation, inverse Polish (postfix), ternary formula, quaternary formula
51 micro database systems engineer jobs
"3 Algorithms and Data Structures" important test center
- Algorithm four basic characteristics: feasibility, uncertainty, have poor resistance, input and output.
- Data Structure three elements: the logical structure of data in the data storage structure, the operation of the various data structures.
- Stack: last in, first out (LIFO, last in first out). Queue: First In First Out (FIFO).
- Circular queues: queue the number of element calculation cycles n = (rear-front + MAXSIZE) mod MAXSIZE
- Special Matrix: The symmetric matrix, triangular matrix, the row order are sequentially stored diagonal matrix and the like.
- Binary tree traversal: preorder traversal (DLR), inorder traversal (LDR), postorder traversal (LRD)
- Huffman tree Huffman (optimal binary tree): structure, Huffman coding, a binary search tree
- FIG basic concepts: the calculation of the edge
- FIG sequentially stored (the adjacency matrix), a chain storage (adjacency list)
- Common time searching and sorting algorithm complexity
51 micro database systems engineer jobs
"4 computer operating system knowledge" important test center
- The basic features of the operating system: concurrent, shared, virtual, asynchronous nature.
- Operating system functions: processor management, file management, storage management, device management, job management.
- Five state of the process: activities ready, still ready, execution state, blocking activity, still blocking (note suspension of meaning)
- Its operation amount signal PV
- Common process scheduling algorithm: First Come First Served FCFS, short job process priority scheduling algorithm SJ (P) F, in response to a high priority than Round Robin algorithm, time slice, multi-level feedback queue scheduling
- Generating four requirements must have deadlock: exclusive condition and holding condition request, not deprivation, wait loop.
- The basic method of handling deadlock: security queues bankers algorithm, the relationship between resources and the number of processes, detection (resource allocation map), lifted.
- Storage management solutions include: storage management and free partition, its missing pages paged memory management
- Virtual memory page replacement algorithm: the best replacement, FIFO, least recently used
- I / O control: Program I / O, interrupt I / O, the DMA control I / O, the control channel I / O
- Disk Scheduling: FCFS first-come, first-served, SSTF Seeking shortest priority, SCAN, CSCAN
- UNIX commonly used commands, UNIX file permissions and security
51 micro database systems engineer jobs
"5 computer network infrastructure" important test center
- Signal: digital signals, analog signals, analog to digital conversion
- Open Systems Interconnection Reference Model (OSI / RM): physical layer, data link layer, network layer, transport layer, session layer, layer, application layer representation.
- TCP / IP architecture consists of four layers: a network interface layer and the Internet layer, a transport layer, an application layer.
- TCP / IP protocol suite: TCP, UDP, IP, ICMP, ARP, RARP.
- Internetworking device: hubs and repeaters, bridges and switches, routers (the network layer protocol conversion and the following layers), a gateway.
- Collision domains and broadcast domains
- IP address, subnet mask, VLSM Variable Length Subnet
- The domain DN (Domain Name): the role, composition, top-level domain, regional domain names, DNS Domain Name Service
- INTERNTE applications: Telnet, SMTP, POP3, WWW, HTTP, HTML, Uniform Resource Locator URL, FTP, TFTP, FS, SNMP
- Information Systems basic need for security: confidentiality, integrity, availability, controllability and verifiability.
- Firewall Architecture: packet filtering router, a dual-homed host, screened host gateway, is the subnet mask ( "DMZ" concept demilitarized zone)
51 micro database systems engineer jobs
"6 database technology" important test center
- And development of data management technology: artificial management, file system, database management system
- It features database system: structured data; data sharing high, low redundancy, easy to expand; high data independence; unified data management and control by the DBMS
- Database System Structure: Structure three mode (outer mode, mode, the mode), two images (outer mode / mode, mode / intra modes), two independent (logical independence, physical independence)
- Categorical attributes: simple attributes, composite properties, single-valued, multi-valued attribute, NULL attribute, derived attributes
- ER Legend: square, oval, linear, weak entity, specialization
- Common logic model: hierarchical model, network model, relational model, object-oriented model
51 micro database systems engineer jobs
"7 Relational Database" important test center
- Database integrity Type: entity integrity, referential integrity, the integrity of the user-defined
- 5 basic operational relationship: selection, projection, and the difference, Cartesian product
- The traditional set operations: union, intersection, difference, Cartesian product (note that the characteristics of various calculations involved in the relationship)
- Special relational operators: selection, projection, is connected, in addition, the external connection
- Moto组 operation given area operation
- Query Optimization five basic heuristic rules
- Armstrong axiom: reflexive law, augmented law, passed law, derivation rules: merge, break down, pseudo-pass
- Calculating a candidate code
- 1NF、2NF、3NF、BCNF、4NF
- And holding functional dependency lossless join
51 micro database systems engineer jobs
"8 SQL Language" important test center
- CREATE TABLE、CREATE VIEW
- Data manipulation: INSERT, UPDATE, DELETE
- SELECT: join query, the query packet, subqueries (associated with the non-associated), a set of query
- GRANT、REVOKE
- Stored Procedures (transaction processing, use cursors), triggers
51 micro database systems engineer jobs
"9 system development and operational knowledge" important test center
- Software life cycle phases: the definition phase (problem definition, feasibility analysis, needs analysis), stage of development (outline design, detailed design, coding, implementation, testing), the maintenance phase (use and maintenance, eliminated).
- Software development methods: structured approach, Jackson method, prototyping, object-oriented methods, agile methods.
- Gantt chart (Gantt chart), the PERT network, the Capability Maturity Model (CMM).
- Data flow diagram (DFD), data dictionary (DD), UML
- The basic principle of the divided modules: high cohesion, low coupling
- Test System: dynamic, static, black box, white box
- System Conversion: Direct conversion, parallel conversion, segmented converter.
51 micro database systems engineer jobs
"Database Design 10" important test center
- The basic steps Orleans (New Orleans) database design method: requirement analysis, conceptual design, logical structure design, physical structure design
- Data abstraction: classification is member of, aggregation is part of, is subset of generalization
- ER diagram of an integrated conflict classification: two types of attributes conflict, two types of naming conflicts, structural conflicts categories
- Problem ER diagram to relational model of conversion to be solved: how to convert the links between entities and entity relationship model type, how to determine the relationship between these properties and code patterns.
- Routine database maintenance: maintenance of database reorganization and reconstruction, maintenance view, the document
51 micro database systems engineer jobs
"11 Transaction Management" important test center
- ACID properties of transactions: atomicity, consistency, isolation, durability
- The type of failure and recovery: internal transaction failures, system failures, media failures, computer viruses
- Concurrent operation of destroying the isolation of affairs leads to inconsistencies in the database data, there are four categories: lost updates, non-repeatable read, read dirty data, read Phantom.
- Log and checkpoint technology
- The main technical concurrency control is blocked: three locking protocol, two locking protocol, a one-time locking protocol
51 micro database systems engineer jobs
"12 database development and new technology" important test center
- DDB's architecture: a global layer, the overall conceptual model, fragmentation mode, split mode, the concept of partial layers, an inner layer partially
- Distribution of the transparency of DDB: fragmentation transparency and location transparency, the transparency of the local data model
- Data slice must comply with three principles: completeness condition, reconfigurable conditions, conditions disjoint
- Distributed transaction commits: 2PC, 3PC
- XML and database: Data exchange points, template-driven, model-driven
- Object-oriented data model for five basic concepts: objects, classes, inheritance, object identity and object nested
- Represents the target line represents the value represents, represents an array of values, a list of values, represents a multi-set value, set of values: complex data type definition
- Data warehouse has four basic characteristics: subject-oriented, integrated, non-renewable, ever-changing with time.
- DW data transfer: a simple transfer, cleaning, integration, aggregation and generalization
- DM analysis: association, sequence mode, classification, clustering, outlier analysis, regression analysis
- NoSQL is not required to meet the ACID, the need to satisfy Base (weak consistency theory, only requires eventual consistency) can be.
- Typical NoSQL database: document storage, key storage, graphics memory, multi-valued
51 micro database systems engineer jobs
"13 Standardization and Intellectual Property Rights" important test center
- Character of Intellectual Property: non-material, exclusive, regional, timeliness
- The extent of adoption of international standards or foreign advanced standards in our country: the use of identical, equivalent to, is not equivalent to
- Software Capability Maturity Model CMM: the initial level, repeatable level, defined level, management level, optimization level
- Licensing of software copyright: exclusive license, exclusive license, general license
- Computer software copyright protection (50 years): a natural person, cooperative development, legal persons or other organizations
- Service development software copyrights, commissioned the development of copyright
- Patent application principles: the principle of patent application includes a written application principle, first apply the principles and priority principles.
- Trademark features of intellectual property rights: specific resistance (specific resistance), regional and temporal.