ORACLE PL/SQL Instance fine solutions in the first chapter PL/SQL Concepts

1. Traditional layer by layer data, and Plsql as a separate unit to return to the client, reduce the query, reduce the network transmission of the round trip, funny

2.pl/sql statement blocks are divided into two types: naming (subroutines, functions, packages that exist in the database, and later can be referenced by name), Anonymous

Difference: A named statement block is stored in a database, referenced by a name, and an anonymous statement block does not have a name, does not exist in the database, and cannot be referenced later

The PL/SQL statement block is divided into three parts: declaration, executable (executable must exist), exception

A declaration is a definition of a variable, a constant, a semicolon, a definition of an identifier, a normal amount, and a cursor reservation declare

Executable is a reserved word begin and end and select. A.. Into. V_a. From XX is to assign the value of a query to the variable v_a

Exception: reserved word exception

5. How to perform PL/SQL

5.1 Substitution variables in front of the variable & or && A: = &b, with the substitution of variables because the PL/SQL statement block can receive input information, cannot enter a value, not divided into any space

ORACLE PL/SQL Instance fine solutions in the first chapter PL/SQL Concepts