Oracle ORA 02149 exception capture

A stored procedure is a set of SQL statements that are designed to accomplish a specific function.

set, which is compiled and stored in a database. The user does this by specifying the name of the stored procedure and giving the parameters.

if the stored procedure has arguments) to execute it. Stored procedures are an important part of a database.

objects, any well-designed database application should use stored procedures.

A stored procedure is a process that is compiled and optimized by flow control and SQL statement writing.

It is stored in the database server and can be called by the application when it is used. In Oracle, several related processes can be grouped together to form a package.

Stored procedures are only compiled at the time of creation, and they do not need to be recompiled every time they are executed in the future, while general SQL statements are compiled every time they are executed, so the use of stored procedures can improve the execution speed of the database.

When performing complex operations on a database, such as update, insert, query, or delete multiple tables, this complex operation can be encapsulated with stored procedures in conjunction with the transaction processing provided by the database.

The storage process can be reused, reducing the workload of database developers.

High security, you can set that only a user has the right to use a specified stored procedure.

String connectors.

For example:'aaa' ||'bbb' = 'aaabbb'

Oracle Database, also known as Oracle RDBMS, or simply database system is a group of software products with distributed database as the core provided by Oracle Corporation (Oracle) in the United States, and is one of the most popular client server or BS architecture databases. For example, Silverstream is a type of middleware based on databases. Oracle database is currently the most widely used database management system in the world, as a general database system, it has complete data management functions; As a relational database, it is a product of complete relationships; As a distributed database, it implements distributed processing capabilities.

But all of its knowledge, as long as you learn Oracle knowledge on one model, you can use it on all types of machines.

A kind of database.

It's like: MySQL

It's quite popular and high-end.

A database produced by Oracle.

(+) is the connection.

For example, select a*,b.* from a(+)= b is a right connection, which is equivalent to select a*,b.* from a right join b

select a.*,b.* from a = b(+) is a left join, which is equivalent to select a*,b.* from a left join b

Namely" (+"The other side of the position is the direction of the connection, and when you connect the full collection with the partial collection, you should put a (+) after the column of the partial collection to achieve a null effect when there is no match.

Got it?

Whichever side has (+) is allowed to be empty.

There (+ means that there is a subtable.)

$ In oracle is commonly found in:

1.Regular expressions:

It denotes the end of a line, such as:

sql> select description, regexp_instr(description,'ing$') where_it_is

2 from testtable

3 where regexp_instr(description,'ing$') >0;

description where_it_is

2003 movie showing 16

2.System View Pseudo Table:

For example: x$ktfbue

v$session

These are maintained by the system and cannot be modified by the user.

It should represent the current parameter values that are variable.

For example, $today represents today's date.

(+) in oracle is a special usage, (+ denotes an outer join, and is always placed on the side of the non-primary table.

For example, left outer join:

select , from a left join b on ;

equivalent to select , from a, b where = ;

As another example, this time it's the right outer join:

select , from a right join b on ;

equivalent to select , from a, b where = ;

Remember to give points if you understand!

1 oracle means database.

2SQL is a statement that operates a database, and the database is made by many companies, such as the common MySQL

Oracle Data, which is a database developed by two different companies.

As people who use databases, we need to learn SQL to operate this database.

Let's take an analogy.

oracel

And mysql is like BMW and Mercedes-Benz, these two cars are produced by companies that don't understand, as our users, that is, people who buy cars, they must learn to drive, this driving is like a SQL statement, just to operate the car.

select * from a,b

The meaning of where here is that table A and table B are connected, table A is displayed first, and then table B whose ID is the same as table A is connected, and those that do not have are filled with some spaces at the end.

This means left connection, or right connection, simple explanation:

The table structure is as follows.

id name job01 jack cleck02 owen

03 awer work, the owen name in the above structure corresponds to the job column, there is no content, if you want to investigate that one party has data and the other party has no data, you need to use the connection.

Outer join symbols.

Statements like left join, right join.

Left connection, or right connection.

As; select * from shop a ,shopgoods b where stands for left connection!

There is no such thing in oracle, only this: = is equivalent to =, which is an assignment operator.

Written backwards, it should be :=, which means assignment.