oracle sql certification book

Label:Oracle command-line tools basic operations and SQL commands1. Basic Concepts1.1. Data typeBasic data Type (number,varchar2,date)O Racel supports the following internal data types:VARCHAR2 variable length string with a maximum of 2000 characters.Number numeric.Long to longer character data, up to 2G bytes.Date type.RAW binary data, up to 255 bytes in length.Long RAW variable-length binary data with a maximum length of 2G bytes.ROWID 26 binary str

Tags: visible test current access think analysis grouped spreadsheet rulesOne: Download routeII: Book DrawingThree: Catalogue The 1th Chapter SQL core1.1 SQL language1.2 Interface of the database1.3 Sql*plus Review1.3.1 Connecting to a database1.3.2 Configuring the Sql*p

from the database table, you must use the Top keyword. If the Select statement contains both top and order by statements, it is selected from the sorted result set. For example: Select top 10 * from Table Name The data retrieval method described today allows you to retrieve records from rows m to n in a table at will, and implement paging using SQL statements. If you need to try it, I will not explain it here... 2.

in the world, almost 85% of them use DB2 database servers, and about 5% in China to 97 years. Scalability and concurrency: SQL ServerThe parallel implementation and coexistence model are not mature. It is difficult to process the increasing number of users and data volumes. Limited scalability.OracleThe parallel server enables a group of nodes to share the work of the same cluster to expand the capabilities of the windoupstream, providing high-availa

Imitating the example of Oracle performance diagnostics in two experiments, the book says that if you don't use relies_on, the change action on the object that the function depends on does not cause the result cache to fail operation (Result_cache relies_on (test1, TEST2), the test proves wrong, the function F1 () does not use relies_on, but the changes on the table affect the function. C:\Documents and Set

PL/SQL single-line functions and group functionsA function is a program that has 0 or more parameters and has a return value. Oracle has built a series of functions in SQL, which can be called SQL or PL/SQL statements, and functions are divided into two main categories:Singl

Reprinted from: http://www.cnblogs.com/tianqing/archive/2008/06/25/1229419.htmlOracle database structure comparison, comparison of specific details of the differences, such as: 2 libraries specific to those tables, different where, the primary key, length, type ..., the requirement is a SQL implementation, for me, this SQL rookie, is a challenge. Fortunately, there is a

is much higher than that of the composite Index query efficiency, while in 11.2.0.3 version Verify that the ad hoc query efficiency of the common composite index is more efficient than the efficiency of the bitmap index) Create TableT (name_id, gender not NULL, location not NULL, Age_range not NULL, data) as Selectrownum, Decode ( Floor(Dbms_random.value (0,2)),0,'M',1,'F') gender, Ceil (Dbms_random.value (0, -) Location , decode ( Floor(Dbms_random.value (0,4)),0,' Child',1,' Young',2,'Middle

Oracle Database primary key auto-increment SQL We all know that in MySQL, it is very easy to implement automatic increment of primary keys. you only need to add auto_increment after the primary key definition, but this is not the case in Oracle. It takes several steps to complete 1. create table account book (account I

; --() Select NVL (score,10) score from student;RowNum related--rownum is less than a certain number can be directly as a query condition (note that Oracle does not support select top) SELECT * from student where rownum --efficiency is much higher than the way onePaging Query(assuming 10 per page)Does not contain a sort:-Low Efficiency SELECT * FROM (select RowNum rn, d.* from Djdriver D ) p where p.rnSELECT * FROM (select RowNum rn, d.* from Djdrive

... 2. Oracle I just got in touch with it. I don't know much about it, but the language has the same points. I just want to learn something different. For Oracle, The rownum keyword is used to extract 10 records from the database table. For example, to retrieve 10 records from Table A (whose primary key is ID), the statement is as follows: Select * from a where rownum The

Label:OracleOracle can run on all major platforms (including Windows). Full support for all industry standards. Adopt a fully open strategy. Enables customers to choose the solution that best suits them. Full support for developers, Oracle parallel servers extend the capabilities of Windows NT by enabling a set of nodes to share work within the same cluster, providing a solution for high availability and highly scalable clusters. If Windows NT does no

equivalent to a select statement. A graph is a SQL statement that does not occupy space. Using view does not improve performance, but simplifies SQL statements.(Extended knowledge: new charts after oracle 8i) MV materialized views (occupying storage space, there is a space for the select results, which will improve the query view and enhance real-time performanc

';A graph is equivalent to a select statement. A graph is a SQL statement that does not occupy space. Using view does not improve performance, but simplifies SQL statements.(Extended knowledge: new charts after oracle 8i) MV materialized views (occupying storage space, there is a space for the select results, which will improve the query view and enhance real-ti

SQL: Oracle 11g create table, function, trigger, sequence, 11 gtrigger -- Place directory drop table BookPlaceList; create table BookPlaceList (BookPlaceID int primary key, -- NUMBERBookPlaceName nvarchar2 (500) not null, BookPlaceCode varchar (100) null, -- location parameter BookPlaceParent INT null -- BookPlaceKindId nvarchar (500) null -- place DIRECTORY parameter ID); select * from BookPlaceList; --- a

largest companies use DB2 database servers, while the country accounts for about 5% of the 97. scalability, parallelism SQL Server Parallel implementation and coexistence models are not mature. It is difficult to handle the increasing number of users and data volumes. Scalability is limited. Oracle Parallel Servers Extend Window NT's capabilities by enabling a set of nodes to share work in the same clust

number of users and data volumes. Scalability is limited. Oracle Parallel Servers Extend Window NT's capabilities by enabling a set of nodes to share work in the same cluster, providing high-availability and highly scalable clusters of solutions. If WindowsNT does not meet the needs, users can move the database to UNIX. The DB2 DB2 has good parallelism. The DB2 extends the database management to the parallel, multi-node environment. A database part

much stronger than Oracle. However, the stability and reliability of the Windows operating system are obvious to all, and Microsoft's strategic goal is to lock customers into the Windows Platform environment, and SQL Server can be improved only with the improvement of Windows performance. From the operational platform, Oracle is completely superior to

increasing number of users and data volumes. Scalability is limited. Oracle Parallel servers extend the capabilities of Windows NT by enabling a set of nodes to share work in the same cluster, providing high-availability and highly scalable clusters of solutions. If WindowsNT does not meet the needs, users can move the database to UNIX. DB2 DB2 has a good parallelism. The DB2 extends the database management to the parallel, multi-node environment.

largest companies use DB2 database servers, while the country accounts for about 5% of the 97. scalability, parallelism SQL Server Parallel implementation and coexistence models are not mature. It is difficult to handle the increasing number of users and data volumes. Scalability is limited. Oracle Parallel Servers Extend Window NT's capabilities by enabling a set of nodes to share work in the same clus