Block

The block, which groups related declarations and statements, is the basic unit of a PL/SQL source program. It has an optional declarative part, a required executable part, and an optional exception-handling part. Declarations are local to the block and cease to exist when the block completes execution. Blocks can be nested.

An anonymous block is an executable statement.

Topics:

Syntax
Semantics
Examples
Related Topics

Syntax

plsql_block ::=

Description of the illustration plsql_block.gif

See body ::=.

declare_section ::=

Description of the illustration declare_section.gif

See item_list_2 ::=.

item_list_1 ::=

Description of the illustration item_list_1.gif

See:

item_list_2 ::=

Description of the illustration item_list_2.gif

See:

type_definition ::=

Description of the illustration type_definition.gif

See:

subtype_definition ::=

Description of the illustration subtype_definition.gif

item_declaration ::=

Description of the illustration item_declaration.gif

See:

pragma ::=

Description of the illustration pragma.gif

See:

body ::=

Description of the illustration basic_body.gif

See exception_handler ::=.

statement ::=

Description of the illustration statement.gif

See:

plsql_block ::=
procedure_call ::=
sql_statement ::=

procedure_call ::=

Description of the illustration procedure_call.gif

sql_statement ::=

Description of the illustration sql_statement.gif

Semantics

assignment_statement

See "Assignment Statement".

base_type

The base type of the subtype that you are defining. The base type can be either a predefined PL/SQL scalar data type (or subtype) or an existing user-defined subtype. For information about predefined scalar data types, see "Predefined PL/SQL Scalar Data Types and Subtypes". For information about user-defined subtypes, see "User-Defined PL/SQL Subtypes".

basic_loop_statement

See "Basic LOOP Statement".

BEGIN

Starts the executable part of the block, which contains executable statements.

case_statement

See "CASE Statement".

collection_method_call

A call to one of these collection methods, which are procedures:

DELETE
EXTEND
TRIM

For syntax, see "Collection Method Call".

continue_statement

See "CONTINUE Statement".

close_statement

See "CLOSE Statement".

commit_statement

SQL COMMIT statement. For syntax, see Oracle Database SQL Language Reference.

constraint

The constraint on the base type of the subtype that you are defining.

Restriction on constraint Do not specify constraint if the base type cannot specify either a maximum size or a precision and scale.

cursor_for_loop_statement

See "Cursor FOR LOOP Statement".

DECLARE

Starts the declarative part of the block, which contains local declarations. Local declarations exist only in the current block and its sub-blocks and are not visible to enclosing blocks.

delete_statement

SQL DELETE statement. For syntax, see Oracle Database SQL Language Reference. See also "DELETE Statement Extension".

END

Ends the block.

EXCEPTION

Starts the exception-handling part of the block. When an exception is raised, normal execution of the block stops and control transfers to the appropriate exception_handler. After the exception handler completes, execution resumes with the statement following the block. For more information about exception-handling, see Chapter 11, "PL/SQL Error Handling."

exception_handler

See "Exception Handler".

execute_immediate_statement

See "EXECUTE IMMEDIATE Statement".

exit_statement

See "EXIT Statement".

fetch_statement

See "FETCH Statement".

for_loop_statement

See "FOR LOOP Statement".

forall_statement

See "FORALL Statement".

goto_statement

See "GOTO Statement".

if_statement

See "IF Statement".

insert_statement

SQL INSERT statement. For syntax, see Oracle Database SQL Language Reference. See also "INSERT Statement Extension".

label

An undeclared identifier. If a block or statement has multiple labels, they must be unique for that block or statement.

lock_table_statement

SQL LOCK TABLE statement. For syntax, see Oracle Database SQL Language Reference.

name

The name of the block to which END applies—a label, function_name, procedure_name, or package_name.

null_statement

See "NULL Statement".

open_statement

See "OPEN Statement".

open_for_statement

See "OPEN FOR Statement".

( parameter [, parameter ]... )

List of actual parameters for the procedure being called. The data type of each actual parameter must be compatible with the data type of the corresponding formal parameter (see Table 3-10, "Possible Implicit PL/SQL Data Type Conversions"). If the procedure specifies an initial value for a parameter, you can omit that parameter from the parameter list.

If the procedure has no parameters, or specifies an initial value for every parameter, you can either omit the parameter list or specify an empty parameter list.