Oracle

CREATE OR REPLACE Package pak_02 is--Header--Here you can define public parameter function fun_01 RETURN number; PROCEDURE pro_01; END; CREATE OR REPLACE Package Body pak_02 is----Here you can define a private variable function fun_01 return number

Create or Replace procedurePr_test1 isV_case Number(3) := -;--Defining Variablesbegin--/ * Judgment Statementif 2>1 ThenDbms_output.put_line ('conditions established'); ElseDbms_output.put_line ('conditions are not tenable'); End if; if 21

Dual is the smallest worksheet provided by Oracle, with a single row and some special functions.Regardless of what you do (don't delete records), it has only one record-' X '.Role:1. Select evaluates constant expression and pseudo-column equivalence.

The set operator is specifically used to combine the results of multiple SELECT statements, including: Union, union All, INTERSECT, minus. When you use the SET operator, you must ensure that the number of columns in different queries matches the

　　One, the Oracle large_pool_size size setting value how muchJava_pool_size:Specifies, in bytes, the size of the Java storage pool, which is used to store Java methods and classes that define representations in shared memory, and Java objects that

Oracle queries recently executed SQL statements select Sql_text,last_load_time from V$sql order by last_load_time Desc;SELECT Sql_text, last_load_time from V$sql WHERE last_load_time are not NULL and sql_text like ' select% ' ORDER by Las

Views (view)A view is also known as a virtual table, which is a logical representation of a set of data.The view corresponds to a SELECT statement, and the result set is given a name, which is the name of the view.The view itself contains no data,

Original address: http://blog.csdn.net/shangboerds/article/details/43983791--StartOne thing that these keywords have in common is that they are generally used in sub-queries. Everyone is familiar with in and EXISTS, here I do not introduce, below we

* Some here to satisfy one of the meanings, is to use or string up the comparative clauses.* Any also means satisfying one of the meanings, is also the use of or string up the comparative clauses, the difference is that any is generally used in the

1,rownum is a virtual column that must be used with 1 to use, RowNum = 1,rownum 2,if case loop To add end to ending, end if;3, foreign key, foreign key (s) references table_name (PK)4, create a table, copy the contents of Create table t_1 as SELECT

Common data types for Oracle databasesAll Oracle data types are available in 26 categoriesCharFixed-length string type length is invariant, for example: No char (10) If the value of the deposit is less than 10 characters, the other bits are also

Active Database DuplicationBrief introduction---------The Active database duplication feature is a new feature introduced from 11g that compares the backup set-based replication database functionality in previous versions.The following is a brief

Same point:1.truncate and delete without a WHERE clause, and drop deletes the data in the table.2.drop, truncate are DDL statements (data definition language) that are automatically committed after execution.Different points:1. Truncate and delete

Oracle generates tens of thousands of test dataPeople doing database development or management often want to create a large number of test data, there will be tens of thousands of things, if one entry, it will waste a lot of time, this article

OneWhat to use the package? In a large project, there may be many modules, and each module has its own processes, functions, and so on. And these procedures, functions are put together by default (such as in PL/SQL, the process is put together by

1, to unlock the userAlter user Scott account unlock;2, log off, disconnect, switch the current user connectionQuitConn Scott/tiger3, User rights queryA. View all Users:SELECT * from Dba_users;SELECT * from All_users;SELECT * from User_users;B. View

General completion of import oracle.jdbc.driver.*; After the meeting is declared, you will find an error. Then, you need to:First, the JDBC drive to ClasspathTwo different methods. One is graphical, computer-Properties-Advanced settings-Environment

ORA-12514: TNS: The Listener currently cannot identify the Service requested in the connection Descriptor When PL/SQL is connected to the Oracle database, the error "ORA-12514: TNS: The Listener currently cannot identify the Service requested in the

In-depth analysis of saving and reading mybatis oracle BLOB fields, mybatisblob 1. BLOB Field BLOB refers to the writing of a Binary Large Object, that is, the English Binary Large Object, and CLOB refers to the writing of a Large Character Object,

Sort values in different columns based on conditions. Sometimes the ordering requirements are complex. For example, if a leader is more interested in employees with salaries between 1000 and 2000 yuan, the employees with salaries in this range must