Database face questions
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1. The following is a description of the correct ______.
A, the efficiency of the algorithm implementation has nothing to do with the data storage structure
B, the algorithm is the space complexity algorithm program instructions (or statements) of the Article Number
C, the algorithm is the finite nature of the implementation algorithm must terminate after a finite number of steps
D, none of the above three descriptions
2. The following data structures are not linear data structure is ______. A, Queue B, the linear form C, a binary tree D, Stack
3. In the first five layers of binary tree nodes at most ______. A, 8 B, 16 C, 32 D, 15
4. The following description, consistent with structured programming style is ______.
A, using sequence, selection, and repetition (cycle) of three basic control structures that control of the program logic
B, the module has only one entrance, you can have multiple exit
C, focus on improving the performance of programs D, do not use goto statement
5. The following concept, not object-oriented approach is ______.
A, object B, inherits C, Class D, procedure call
6. In the structured approach, using data flow diagram (DFD) tools as described in the software development phase is ______.
A, viability of B, needs analysis C, the detailed design of D, procedure code
7. In software development, following the design phase of the task is not ______.
A, data structure design B, given the system module structure C, the definition module algorithm D, define requirements and build the system model
8. Database system is the ______.
A, data model B, the database management system, C, software tools D, database
9. The following statements is correct ______.
A, the database is an independent system, no operating system support
B, the database design is the design of database management system
C, the fundamental goal of database technology is to address the problem of data sharing
D, database system, the physical structure of the data must be consistent with the logical structure
10. The following model, the database can be given physical access physical storage structures and methods of the ______.
A, in mode B, outside the model C, the conceptual model D, the logical model
11. Visual FoxPro database file is ______.
A, storage of user data file B, management of database objects in the system files
C, storage of user data and system of documents D, the first three claims are all
12. SQL statement in order to modify the table structure is ______.
A, MODIFY TABLE B, MODIFY STRUCTURE C, ALTER TABLE D, ALTER STRUCTURE
13. If you want to create a data set group report, the first grouping expression is "department", the second group expression is "gender", and the third group is the expression "basic wages", the current index of the index expression should be ______.
A, the basic wage sector + sex + B, sector + sex + STR (minimum wage)
C, STR (basic salary) + Sex + department D, sex + departments + STR (minimum wage)
14. To compile a project into an application, the following description of the right is ______.
A, all the project files will be combined into a single application file
B, contains the files of all projects will combine into a single application file
C, the paper will exclude all items combined into a single application file
D, selected by the user's project file will be combined into a single application file
15. Database DB, a database system DBS, database management system DBMS is ______. relationship between
A, DBS, including DB and DBMS B, DBMS, including DB and DBS
C, DB, including DBS and DBMS D, DBS is the DB, that is DBMS
16. In the "Options" dialog box "File Locations" tab you can set ______.
A, form the default size of B, the default directory
C, date and time display format D, the color code
17. To control the two tables of data integrity and consistency can be set to "referential integrity" and demanded the two tables ______.
A, is a database with two tables B, two tables in different databases
C, two free sheet D, the other one is a free form database table
18. Locate the first record on the command is ______.
A, GO TOP B, GO BOTTOM C, GO 6 D, SKIP
19. In the relational model, to achieve "the same relationship does not allow for tuple" bound by ______.
A, candidate key B, the primary key C, foreign key D, super key
20. Set the current database of 10 records (records without any index), in the following three cases, the current record number is 1; EOF () is true; BOF () is true, the command? RECN () The results are ______.
A, 1,11,1 B, 1,10,1 C, 1,11,0 D, 1,10,0
21. The following expressions result is not the date type is ______.
A, CTOD ("2000/10/01") B, (^ 99/10/01) +365 C, VAL ("2000/10/01") D, DATE ()
22. Only the records meet the join condition only included in the query results, that connect to ______.
A, left join B, the right connection C, the internal connection D, fully connected
23. Index field value is not the only, the index should be chosen type ______.
A, primary index B, General Index C, candidate for the index D, unique index
24. Implementation of the selected work area SELECT 0 result ______.
A, selected work area 0 # B, choose a work area free of the smallest
C, shut down the work area choose D, select the open work area
25. Remove the tables from the database command is ______.
A, DROP TABLE B, ALTER TABLE C, DELETE TABLE D, USE
26. DELETE FROM S WHERE Age> 60 statement function is ______.
A, completely removed from the S table, the records were more than 60 years old B, S in the table were more than 60 years of records are added to delete tag
C, remove the S table D, the age of the table column delete S
27. SELECT-SQL statement is ______.
A, select the work area Statements B, data query C, the selection criteria statement D, the data modification statement
28. SQL language is the ______ language. A, hierarchical database B, the network database, C, relational database D, non-database
29. In SQL, delete the view with ______.
A, DROP SCHEMA command B, CREATE TABLE command C, DROP VIEW command D, DROP INDEX command
30. Following a non-container type control is ______. A, Form B, Label C, page D, Container
31. The query results should be used on the array ______ phrase.
A, INTO CURSOR B, TO ARRAY C, INTO TABLE D, INTO ARRAY
32. The implementation of SQL command in the command window, if the order to occupy multiple lines, line-continuation character is ______.
A, colon (:) B, a semicolon (;) C, a comma (,) D, hyphen (-)
33. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
The library management database, the query 0001 library card readers by name and the title of the book.
SQL statement is correct is ______.
SELECT name, title FROM borrow, books, readers WHERE;
Borrow. Library Zhenghao = "0001" AND;
______
______
A, Library. The total number = borrow. The total number AND;
Readers. Library Zhenghao = borrow. Library Zheng Hao
B, book. CLC = borrow. CLC AND;
Readers. Library Zhenghao = borrow. Library Zheng Hao
C, the reader. The total number = borrow. The total number AND;
Readers. Library Zhenghao = borrow. Library Zheng Hao
D, books. The total number = borrow. The total number AND;
34. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
The library management database, all units were calculated to borrow books present the reader visits. The following SQL statement is correct is ______.
SELECT unit ,______ FROM borrow, readers WHERE;
Borrow. Library Zhenghao = reader. Library Zhenghao ______
A, COUNT (loan. Library The certificate number ) GROUP BY Unit B, SUM (loan. Library The certificate number ) GROUP BY unit
C, COUNT (loan. Library The certificate number ) ORDER BY Unit D, COUNT (loan. Library The certificate number ) HAVING unit
35. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
The library management database, search borrow the "foundation of modern network technology," a book of library The certificate number . The following SQL statement is correct is ______.
Lending library Zhenghao SELECT FROM WHERE = total number;
______
A, (SELECT FROM books WHERE title library Zhenghao = "Modern Network Technology")
B, (SELECT FROM books WHERE title total number = "Modern Network Technology")
C, (SELECT borrow library Zhenghao FROM WHERE title = "Modern Network Technology")
D, (SELECT number FROM total WHERE title = borrowing "of modern network technology base")
Second, fill in the blank
36. Complexity of the algorithm include ______ complexity and space complexity.
37. The logical structure of data storage space in the computer as the data storage format ______.
38. If classified by function, software is usually divided into white-box testing method testing method and ______.
39. If a worker can manage multiple facilities, but only by a worker of a facility management, the entities "workers" and entities "Equipment" link between the ______.
40. Relational database management system to achieve the special relational operators including selection, connection and ______.
41. Command? LEN ("THIS IS MY BOOK") the result is ______.
42.SQL SELECT statement to query results will be stored in the temporary table should be used ______ phrase.
43. Multi-column reports the number of columns can be set by ______.
44. In the Open Project Manager after opening the "Application Builder", you can press ALT + F2 key, the shortcut menu and "Tools" menu ______.
45. Database system is the ______.
46. Query Designer in the "Connection" tab, you can control the choice ______.
47. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
Using SQL in the CREATE command to create a loan form (fields in order to be the same), please fill in the blanks on the following SQL statement:
______
48. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
On the library management database, query by the "Tsinghua University Press" or "electronic publishing industry," published, and unit price does not exceed 20 yuan title. Please fill in the blanks on the following SQL statement:
SELECT title, publishers, Price FROM Books;
WHERE_______ AND;
_______
49. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
Management database of books, find how many books were borrowed. Please fill in the blanks on the following SQL statement:
SELECT _______ FROM Lending
The first set of answers to questions
Multiple Choice
1-5 CCBAD 6-10 BDBCA 11-15 DCBAA 16-20 BAABA 21-25 CCBBA 26-30 BBCCB 31-35 DDAAB
Fill in the blank
36. Time 37. Model or logic model 38. Black box 39. Many or more than one pair or a pair of n or 1: N or 1: n or 1: n or 1: N or a pair of m or 1: M or 1: m or 1: m or 1: N 40. Projection 41.15 42. Into cursor or Into cursor cursorname 43. Page Setup or columns 44. application program generator 45. database management system or DBMS 46. connection type or connection Condition 47. CREATE TABLE to borrow (library Zheng Hao C (4), the total number C (6), library Date D (8)), or CREA TABL borrow (library Zheng Hao C (4), the total number C (6), library Date D (8)) or the CREATE TABLE to borrow (library Zheng Hao C (4), the total number C (6), date library D) or CREA TABL borrow (library Zheng Hao C (4), the total number C ( 6), library date D) 48. Unit <= 20 or (publishing units = "Tsinghua University Press" OR Publisher = "Electronics Industry Publishing House") or (publishing units = "Electronic Industry Press" OR Publisher = "Tsinghua University Press") or (publishing units = 'Tsinghua University Press' OR publishing unit = 'Electronic Industry Press') and (publishing units = "Tsinghua University Press" OR Publisher = "Electronic Industry Press ") or (publishing units = 'Tsinghua University Press') 49. COUNT (DISTINCT total number) or COUN (DISTINCT total number) or COUNT (DIST total number) or COUN (DIST total number)
<br /> A second set of questions, multiple choice
1. The following data structures are not linear data structure is ______.
A, Queue B, the linear form C, a binary tree D, Stack
2. In the structured approach, using data flow diagram (DFD) tools as described in the software development phase is ______.
A, viability of B, needs analysis C, the detailed design of D, procedure code
3. Structured programming the main emphasis is ______.
A, the scale of the program B, program readability C, the performance of programs D, program portability
4. In the software life cycle and can accurately determine the software system must do and must have the function of the stage which is ______.
A, summary of design B, the detailed design C, feasibility analysis of D, needs analysis
5. The following narrative on the correct stack is ______. A, the stack can only insert data B, the stack can only delete data
C, the stack is FIFO linear form D, after the stack is advanced out of the linear form
6. The following does not belong to the principles of software design is ______. A, abstract B, modular C, bottom-up D, the information hidden
7. On the length of the order of N linear table lookup, in the worst case number of comparisons required for the ______.
A, N +1 B, NC, (N +1) / 2 D, N / 2
8. View of the design are generally three kinds of design sequence, the following does not belong to the design view is ______.
A, top-down B, outside-C, from the inside out D, bottom-up
9. The following description of the database, the right is ______. A, the database is a DBF file B, the database is a relational
C, the database is a structured collection of data D, the database is a set of documents
10. The following statement, do not belong to the contents of the data model described is ______.
A, data structure B, data manipulation C, data query D, data constraints
11. In the following Visual FoxPro expression, the operation result is logical really ______.
A, EMPTY (. NULL.) B, LIKE ('acd', 'ac?') C, AT ('a', '123abc ') D, EMPTY (SPACE (2))
12. Expression VAL (SUBS ("Pentium-586", 5,1)) * Len ("visual foxpro") the result is ______.
A, 13.00 B, 14.00 C, 45.00 D, 65.00
13. The following narrative on the free list, the right is ______.
A, all with the previous version of FOXPRO (FOXBASE) the establishment of the table
B, can use Visual FoxPro to establish, but can not add it to the database
C, free form can be added to the database, the database table can be removed from the database to become a free table
D, free form can be added to the database, but database tables can not be removed from the database to become a free table
14. The following data environment and data on the environment, the relationship between two tables in ,______ statement is correct.
A, the data environment is the object relationship is not the object B, the data environment is not an object, the object relations
C, the data environment is the object relationship is the data environment object D, the data environment and the relations are not objects
15. In the "Report Designer", you can use the control is ______.
A, label, field control and line B, label, field control and list box
C, labels, text boxes and list boxes D, layout and data source
16. With two-dimensional table of data to represent the links between entities and entity data model called ______.
A, solid - Contact Model B, hierarchical model C, mesh model D, relationship model
17. Check box to specify the properties of the currently selected state is ______. A, Selected B, Caption C, Value D, ControlSource
18. How to use the menu to open a directory that already exists in the current query file zgjk.qpr, the generation of command in the command window is ____.
A, OPEN QUERY zgjk.qpr B, MODIFY QUERY zgjk.qpr
C, DO QUERY zgjk.qpr D, CREATE QUERY zgjk.qpr
19. Be accompanied by a table to open and automatically open the index is ______.
A, a single index file (IDX) B, composite index files (CDX) C, the composite index file structure D, unstructured composite index file
20. In the database designer, create many relationship between two tables is achieved through the following index ______.
A, "one" table of the main index or candidate index, "multi" general index table
B, "one" table of the main index, "many" table of the general index or the candidate index
C, "one" table of the general index, "many" table of the main index or candidate index
D, "one" table of general index, "many" table of the candidate index or general index
21. The following function, function value of character is ______. A, DATE () B, TIME () C, YEAR () D, DATETIME ()
22. The following description of the right of the control is ______.
A, the user can make multiple choices in the combo box B, the user can make multiple choices in the list box
C, the user can select an option group, option button more than D, the user group within a form check box can only select one of the
23. To determine whether the list box of an entry is selected the properties should be used is ______.
A, Value B, ColumnCount C, ListCount D, Selected
24. With relations R1 and R2, the results obtained through the relational operators S, then S is ______.
A, a relation B, 1 form C, a database D, an array
25. DBAS refers ______. A, database management system B, the database system C, a database application system D, the database service system
26. Set X = "ABC", Y = "ABCD", then the following expression value. T. is ______. A, X = YB, X == YC, X $ YD, AT (X, Y) = 0
27. In the table structure, logic type, date, type, notes, type the width of the field were fixed to ______.
A, 3,8,10 B, 1,6,4 C, 1,8, arbitrary D, 1,8,4
28. In standard SQL, create view command is ______.
A, CREATE SCHEMA command B, CREATE TABLE command C, CREATE VIEW command D, CREATE INDEX command
29. The SCAN loop structure, the correct description is ______.
A, SCAN loop structure of the LOOP statement, program flow can be directed cycle began statement SCAN, first determine EOF () function is true
B, the use of SCAN loop structure, one must open the database
C, SCAN loop structure of the loop statement must be read, SKIP
D, SCAN loop structure, and if omitted the clause, \ FOR, and WHILE conditional clause, directly out of circulation
30. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
The library management database, to query the possession of books, publishers of books in all the highest unit price, average price and number of copies, the following SQL statement is correct is ______.
SELECT publishers ,______,______,______;
FROM librarians! Book publishing units ______
A, MIN (Price) AVGAGE (Price) COUNT (*) GROUP BY B, MAX (Price) AVG (Price) COUNT (*) ORDER BY
C, MAX (Price) AVG (Price) SUM (*) ORDER BY D, MAX (Price) AVG (Price) COUNT (*) GROUP BY
31. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
The library management database, find the CIE units of the number of readers to borrow books.
The following SQL statement is correct is ______.
SELECT ______ FROM loan WHERE;
_______ Library Zheng Hao
A, COUNT (DISTINCT library number)
IN (SELECT FROM User WHERE library Zhenghao units = "CIE")
B, COUNT (DISTINCT library number)
IN (SELECT FROM loan WHERE library Zhenghao units = "CIE")
C, SUM (DISTINCT library number)
IN (SELECT FROM User WHERE library Zhenghao units = "CIE")
D, SUM (DISTINCT library number)
IN (SELECT FOR borrow library Zhenghao WHERE unit = "CIE")
32. Check purchase order number (character, length of 4) Last character is "1" error command is ______.
A, SELECT * FROM Orders WHERE SUBSTR (purchase order number, 4) = "1"
B, SELECT * FROM Orders WHERE SUBSTR (purchase order number, 4,1) = "1"
C, SELECT * FROM Orders WHERE "1" $ purchase order number
D, SELECT * FROM Orders WHERE RIGHT (purchase order number, 1) = "1"
33. In the relational model, in order to achieve "the same relationship is not allowed tuple" bound to be used ______.
A, the temporary keyword B, primary key C, external keyword D, the index keyword
34. According to "workers" project file generated emp_sys.exe application command is ______.
A, BUILD EXE emp_sys FROM employee B, BUILD APP emp_sys.exe FROM employees
C, LIKE EXE emp_sys FROM employees D, LIKE APP emp_sys.exe FROM employees
35. Set the current directory under the current database: College. Dbc, including "teachers" table and "College" form.
"Teacher" table:
"College" table:
A SQL statement:
SELECT DISTINCT Department FROM teachers WHERE No. wages> =;
ALL (SELECT salary FROM teachers WHERE line number = "02")
With the above statement is equivalent to the SQL statement is ______.
A, SELECT DISTINCT Department FROM teachers WHERE No. wages> =;
(SELECT MAX (salary) FROM teacher WHERE line number = "02")
B, SELECT DISTINCT Department FROM teachers WHERE No. wages> =;
(SELECT MIN (salary) FROM teacher WHERE line number = "02")
C, SELECT DISTINCT Department FROM teachers WHERE No. wages> =;
ANY (SELECT salary FROM teachers WHERE line number = "02")
D, SELECT DISTINCT Department FROM teachers WHERE No. wages> =;
SOME (SELECT salary FROM teachers WHERE line number = "02")
Second, fill in the blank
36. If classified by function, software is usually divided into white-box testing method testing method and ______.
37. Database System 3 model were ______ mode, internal and external level model level model.
38. In the worst case, the time complexity of bubble sort is ______.
39. In object-oriented approach, the information hidden by the ______ of the object to be achieved.
40. Relational model of data manipulation that is based on the relationship between the data manipulation, generally ______, add, delete and modify the four operations.
41. Should help file set to copy files to the hard disk Foxhelp.chm need to "Options" dialog box ______ tab settings.
42. TIME () return value data type is the type ______.
43. The effectiveness of rules in defining the field, in the rules of the expression box type ________.
44. Design statements usually include two parts :______ and layout.
45. ______ Means that only join conditions to meet before the records included in the query results.
46. With library management database:
Books (total number C (6), CLC C (8), Title C (16), of C (6), publishing unit C (20), Price N (6,2))
Reader (library Zheng Hao C (4), unit C (8), name C (6), sex C (2), Title C (6), Address C (20))
Borrow (library Zheng Hao C (4), the total number C (6), library Date D (8))
Search book prices at 15 to 25 yuan (including 15 yuan and 25 yuan) between the book's title, author, book value and classification number, the results in ascending order by words.
SELECT title, author, unit price, classification FROM books;
WHERE______;
ORDER BY______;
47. With the following relational table R, S and T:
R (BH, XM, XB, DWH)
S (SWH, DWM)
T (BH, XM, XB, DWH)
Achieve R ∪ T's SQL statement is _______.
48. With the following relational table R:
R (NO, NAME, SEX, AGE, CLASS)
Primary key is the NO
For the Student ID, NO, NAME as name, SEX is sex, AGE is the age, CLASS No. for the classes. Write the following functions of the SQL statement.
Insert "95 031" class student number is 30, the name "Zheng" student records ;_______.
49. With the following relational table R:
R (NO, NAME, SEX, AGE, CLASS)
Primary key is the NO
NO for the school which number (numeric), NAME as name, SEX is sex, AGE is the age, CLASS No. for the classes. Write the following functions of the SQL statement.
Remove the student number is 20 students record ;______.
Second question the answer
1-5 CBBDD 6-10 CBBCC 11-15 DDCCA 16-20 DCBCA 21-25 BBDAC 26-30 CDCBD 31-35 ACBBA
36. Black box 37. Concepts or concept-level 38.n (n-1) / 2 39. Package 40. Query 41. File location 42. Characters or C 43. Logical expression
44. Data source 45. Internal links
46. Price BETWEEN 15 AND 25 or Unit BETW 15 AND 25 or unit price or unit price BETWE 15 AND 25> = 15 and Price <= 25 or unit price> = 15 and Price = <25 or unit price => 15 and Price <= 25 or Price => 15 and Price = <25, or words with words ASC
47. SELECT * FROM R UNION SELECT * FROM T or SELE * FROM R UNIO SELE * FROM T or SELECT * FROM R UNIO SELECT * FROM T or SELE * FROM R UNION SELE * FROM T
48. INSERT INTO R (NO, NAME, CLASS) VALUES (30, "Zheng", "95031") or INSE INTO R (NO, NAME, CLASS) VALUES (30, "Zheng", "95031")
49. DELETE FROM R WHERE NO = 20 or DELE FROM R WHERE NO = 20 or DELE FROM R WHER NO = 20, or DELETE FROM R WHER NO = 20
Oracle face questions Highlights - Technical articles
1. Explain the cold backup and hot backup of the differences and advantages of each solution: hot backup mode for the archiving database, the database is still in working condition when the backup. The cold backup that closed in the database, back up the database for all models. The advantages of hot backup when the backup, the database can still be used and can restore the database to any point in time. Cold backup is that it's quite simple backup and recovery operations, and because of the cold backup of the database can work in non archive mode, the database performance was slightly better than the archive mode. (Because do not have to archive log write hard disk)
2. You have to use backup and restore the database, but you do not control the files, how to solve the problem?
Answer: rebuild control file, with a backup control file clause in the recover command to restore
Database.
3. How to convert init.ora to spfile?
Answer: Use the create spfile from pfile command.
4. Explain the data block, extent, and segment the difference (in this proposal in English terminology)
Answer: data block is the smallest logical database storage unit. When the database object needs more physical storage space, a continuous data block on the form extent. A database object
Of all of the extents is called the object segment.
5. Given the structure of the two methods checklist
Answer: 1. DESCRIBE command
2. DBMS_METADATA.GET_DDL package
6. How to view the database engine error
Answer: alert log.
7. More truncate and delete command
Answer: Both can be used to delete all records in the table. The difference is: truncate is DDL operation and it moves HWK, without rollback segment. And Delete is DML operations, and the need to take a long time rollback segment.
8. Use reason for the index
Answer: quick access to table data block
9. In the STAR SCHEMA given in two tables and the data they contain, respectively
Answer: Fact tables and dimension tables. Fact table contains a large number of major information and dimension tables placed on the fact table describes some of the attributes of information
10. FACT Table on the need to establish what kind of index?
Answer: Bitmap indexes (bitmap index)
11. Give two related constraints?
Answer: the primary key and foreign key
12. How does not affect the premise of the child table, rebuild a parent table
Answer: the child table's foreign key enforcement effectiveness of the reconstruction master table, activate the foreign key
13. Explain the filing and the difference between non-archive mode and their respective advantages and disadvantages
Answer: archive mode means you can back up all database transactions and restore to any point in time. Non-archive mode, by contrast, can not restore to any point in time. But the non-archive mode can bring a little to improve database performance on.
14. How to create a backup control file?
Answer: Alter database backup control file to trace.
15. Given database starts normally experienced in several states?
Answer:
STARTUP NOMOUNT - the database instance starts
STARTUP MOUNT - Database Load
STARTUP OPEN - Open database
16. Which column can be used to distinguish V $ views, and GV $ views?
Answer: INST_ID specified in a cluster environment to the specific instance.
17. How to generate explain plan?
Answer: Run utlxplan.sql. Establish plan table
For a particular SQL statement, using the explain plan set statement_id = 'tst1' into plan_table
View Run utlxplp.sql or utlxpls.sql explain plan
18. How to increase the buffer cache hit rate?
Answer: more busy in the database, the application of buffer cache advisory tool, query v $ db_cache_advice. If it is necessary to change, you can use the command alter system set db_cache_size
19. ORA-01555 in our approach?
Answer: The exact error message is the snapshot too old within rollback seg, usually by
Increase the rollback seg to solve the problem. Course should check the SQL text of the error caused by the specific
20. Explain the $ ORACLE_HOME and $ ORACLE_BASE the difference?
Answer: ORACLE_BASE is the root directory of oracle, ORACLE_HOME is the directory oracle products.
21. How to determine the database's time zone?
Answer: SELECT DBTIMEZONE FROM DUAL;
22. GLOBAL_NAMES set to TRUE to explain the use of
Answer: GLOBAL_NAMES manner specified database connection. If this parameter is set to TRUE, the establishment of the database link name must be linked with the same remote database
23. How to encrypt PL / SQL procedure?
Answer: WRAP
24. Explain FUNCTION, PROCEDURE and PACKAGE difference
Answer: function and procedure is PL / SQL code set, usually in order to complete a task. procedure do not return any value and function will return a value in another
Side, Package is a business function in order to complete a set of function and a collection of proceudre
25. To explain the use of TABLE Function
Answer: TABLE Function through the PL / SQL logic to return a record for the ordinary table / view. They are also used for pipeline and the ETL process.
26. Cite three kinds of three advisory statistics you can collect
Answer: Buffer Cache Advice, Segment Level Statistics, Timed Statistics
27. Audit trace stored in the directory structure in which oracle?
Answer: unix $ ORACLE_HOME / rdbms / audit Windows the event viewer
28. To explain the role of materialized views
Answer: Materialized views are used to reduce the aggregate, the collection and the collection of information on the number of groups. They are usually suitable for data warehouses and DSS systems.
29. When a user process error, which background process is responsible for cleaning it
Answer: PMON
30. What background process refreshes materialized views?
Answer: The Job Queue Processes.
31. How to determine which session is waiting for links and their resources?
Answer: V $ SESSION / V $ SESSION_WAIT
32. Describe what redo logs
Answer: Redo Logs is used for storing database data changes in the situation of physical and logical structure. Can be used to repair the database.
33. How to force LOG SWITCH?
Answer: ALTER SYSTEM SWITCH LOGFILE;
34. Give two methods to judge DDL changes?
Answer: You can use the Logminer or Streams
35. Coalescing done?
Answer: Coalescing for the dictionary-managed tablespace defragment, near the small extents will be merged into a single large extent.
36. TEMPORARY tablespace and a PERMANENT tablespace is the difference?
Answer: A temporary tablespace for temporary objects such as sort structures while permanent tablespaces to store those 'real' object (such as tables, rollback segments, etc.)
37. Create a tablespace automatically created when the database name?
Answer: SYSTEM tablespace.
38. Create a user, what permissions need to give the new user can make it together on the database.
Answer: CONNECT
39. How to increase the data files in the tablespace in?
Answer: ALTER TABLESPACE ADD DATAFILE SIZE
40. How to change the size of data files?
Answer: ALTER DATABASE DATAFILE RESIZE;
41. Which VIEW used to check the data file size?
Answer: DBA_DATA_FILES
42. Which VIEW used to judge the remaining space tablespace
Answer: DBA_FREE_SPACE
43. How to determine who added a record to the table?
Answer: auditing
44. How to reconstruct the index?
Answer: ALTER INDEX REBUILD;
45. Explain what is Partitioning (partition) as well as its advantages.
Answer: Partition large tables and indexes will be split into smaller, easy to manage partitions.
46. You just compiled a PL / SQL Package but there is an error report, how to display an error message?
Answer: SHOW ERRORS
47. How do the various state data collection form?
Answer: ANALYZE
The ANALYZE command.
48. How to start SESSION TRACE level
Answer: DBMS_SESSION.SET_SQL_TRACE
ALTER SESSION SET SQL_TRACE = TRUE;
49. IMPORT and SQL * LOADER these two tools of different points
Answer: These two ORACLE tools are used to import the data into the database.
Difference is: IMPORT tool can only handle generated by another EXPORT ORACLE tools
Data. The SQL * LOADER can import ASCII format of different data sources
50. 2 for the network connection file?
Answer: TNSNAMES.ORA and SQLNET.ORA
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