Rule Types

Table 109-1 DBMS_RULE Types (Page 1 of 2)

Data Structure	Description
"RE$ATTRIBUTE_VALUE Type"	Specifies the value of a variable attribute
"RE$ATTRIBUTE_VALUE_LIST Type"	Identifies a list of attribute values used in a rule evaluation context
"RE$COLUMN_VALUE Type"	Specifies the value of a table column
"RE$COLUMN_VALUE_LIST Type"	Identifies a list of column values used in a rule evaluation context
"RE$NAME_ARRAY Type"	Identifies a list of names
"RE$NV_ARRAY Type"	Identifies a list of name-value pairs
"RE$NV_LIST Type"	Identifies an object containing a list of name-value pairs and methods that operate on this list. This object type is used to represent the event context and the action context for a rule
"RE$NV_NODE Type"	Identifies a name-value pair
"RE$RULE_HIT Type"	Specifies a rule found as a result of evaluation
"RE$RULE_HIT_LIST Type"	Identifies a list of rules found as a result of evaluation
"RE$TABLE_ALIAS Type"	Provides the table corresponding to an alias used in a rule evaluation context
"RE$TABLE_ALIAS_LIST Type"	Identifies a list of table aliases used in a rule evaluation context
"RE$TABLE_VALUE Type"	Specifies the value of a table row using a ROWID
"RE$TABLE_VALUE_LIST Type"	Identifies a list of table values used in a rule evaluation context
"RE$VARIABLE_TYPE Type"	Provides the type of a variable used in a rule evaluation context
"RE$VARIABLE_TYPE_LIST Type"	Identifies a list of variables and their types used in a rule evaluation context
"RE$VARIABLE_VALUE Type"	Specifies the value of a variable
"RE$VARIABLE_VALUE_LIST Type"	Identifies a list of variable values used in a rule evaluation context

RE$ATTRIBUTE_VALUE Type

Specifies the value of a variable attribute.

Syntax

TYPE SYS.RE$ATTRIBUTE_VALUE (
   variable_name       VARCHAR2(32), 
   attribute_name      VARCHAR2(4000),
   attribute_value     SYS.AnyData); 

Attributes

Table 109-2 RE$ATTRIBUTE_VALUE Attributes

Attribute	Description
variable_name	Specifies the variable used in a rule
attribute_name	Specifies the attribute name
attribute_value	Specifies the attribute value

RE$ATTRIBUTE_VALUE_LIST Type

Identifies a list of attribute values used in a rule evaluation context.

Syntax

TYPE SYS.RE$ATTRIBUTE_VALUE_LIST AS VARRAY(1024) OF SYS.RE$ATTRIBUTE_VALUE;

RE$COLUMN_VALUE Type

Specifies the value of a table column.

Syntax

TYPE SYS.RE$COLUMN_VALUE (
   table_alias       VARCHAR2(32), 
   column_name       VARCHAR2(4000),
   column_value      SYS.AnyData); 

Attributes

Table 109-3 RE$COLUMN_VALUE Attributes

Attribute	Description
table_alias	Specifies the alias used for the table in a rule
column_name	Specifies the column name
column_value	Specifies the column value

RE$COLUMN_VALUE_LIST Type

Identifies a list of column values used in a rule evaluation context.

Syntax

TYPE SYS.RE$COLUMN_VALUE_LIST AS VARRAY(1024) OF SYS.RE$COLUMN_VALUE;

RE$NAME_ARRAY Type

Identifies a list of names.

Syntax

TYPE SYS.RE$NAME_ARRAY AS VARRAY(1024) OF VARCHAR2(30);

RE$NV_ARRAY Type

Identifies a list of name-value pairs.

Syntax

TYPE SYS.RE$NV_ARRAY AS VARRAY(1024) OF SYS.RE$NV_NODE;

RE$NV_LIST Type

Identifies an object containing a list of name-value pairs and methods that operate on this list. This object type is used to represent the event context for rule set evaluation and the action context for a rule.

Syntax

TYPE SYS.RE$NV_LIST AS OBJECT( 
   actx_list    SYS.RE$NV_ARRAY);

Attributes

Table 109-4 RE$NV_LIST Attributes

Attribute	Description
actx_list	The list of name-value pairs

RE$NV_LIST Subprograms

This section describes the following member procedures and member functions of the SYS.RE$NV_LIST type:

• ADD_PAIR Member Procedure
• GET_ALL_NAMES Member Function
• GET_VALUE Member Function
• REMOVE_PAIR Member Procedure

ADD_PAIR Member Procedure

Adds a name-value pair to the list of name-value pairs.

Syntax

MEMBER PROCEDURE ADD_PAIR(
   name   IN VARCHAR2, 
   value  IN SYS.AnyData);

Parameters

Table 109-5 ADD_PAIR Procedure Parameters

Parameter	Description
name	The name in the name-value pair being added to the list. If the name already exists in the list, then an error is raised.
value	The value in the name-value pair being added to the list

GET_ALL_NAMES Member Function

Returns a list of all the names in the name-value pair list.

Syntax

MEMBER FUNCTION GET_ALL_NAMES RETURN SYS.RE$NAME_ARRAY;

GET_VALUE Member Function

Returns the value for the specified name in a name-value pair list.

Syntax

MEMBER FUNCTION GET_VALUE(
   name     IN   VARCHAR2) 
RETURN SYS.AnyData;

Parameters

Table 109-6 GET_VALUE Procedure Parameters

Parameter	Description
name	The name whose value to return

REMOVE_PAIR Member Procedure

Removes the name-value pair with the specified name from the name-value pair list.

Syntax

MEMBER PROCEDURE REMOVE_PAIR(
   name    IN   VARCHAR2);

Parameters

Table 109-7 REMOVE_PAIR Procedure Parameters

Parameter	Description
name	The name of the pair to remove

RE$NV_NODE Type

Identifies a name-value pair.

Syntax

TYPE SYS.RE$NV_NODE (
   nvn_name       VARCHAR2(30), 
   nvn_value      SYS.AnyData); 

Attributes

Table 109-8 RE$NV_NODE Attributes

Attribute	Description
nvn_name	Specifies the name in the name-value pair
nvn_value	Specifies the value in the name-value pair

RE$RULE_HIT Type

Specifies a rule found as a result of an evaluation.

See Also: "CREATE_RULE Procedure" "ALTER_RULE Procedure"

Syntax

TYPE SYS.RE$RULE_HIT (
   rule_name              VARCHAR2(61), 
   rule_action_context    RE$NV_LIST); 

Attributes

Table 109-9 RE$RULE_HIT Attributes

Attribute	Description
rule_name	The rule name in the form schema_name.rule_name. For example, a rule named employee_rule in the hr schema is returned in the form hr.employee_rule.
rule_action_context	The rule action context as specified in the CREATE_RULE or ALTER_RULE procedure of the DBMS_RULE_ADM package

RE$RULE_HIT_LIST Type

Identifies a list of rules found as a result of an evaluation.

Syntax

TYPE SYS.RE$RULE_HIT_LIST AS VARRAY(1024) OF SYS.RE$RULE_HIT;

RE$TABLE_ALIAS Type

Provides the table corresponding to an alias used in a rule evaluation context. A specified table name must satisfy the schema object naming rules.

See Also: Oracle9i SQL Reference for information about schema object naming rules

Syntax

TYPE SYS.RE$TABLE_ALIAS IS OBJECT(
   table_alias   VARCHAR2(32),
   table_name    VARCHAR2(194));

Attributes

Table 109-10 RE$TABLE_ALIAS Attributes

Attribute	Description
table_alias	The alias used for the table in a rule
table_name	The table name referred to by the alias. A synonym can be specified. The table name is resolved in the evaluation context schema. The format is the following: schema_name.table_name For example, if the schema_name is hr and the table_name is employees, then enter the following: hr.employees

RE$TABLE_ALIAS_LIST Type

Identifies a list of table aliases used in a rule evaluation context.

Syntax

TYPE SYS.RE$TABLE_ALIAS_LIST AS VARRAY(1024) OF SYS.RE$TABLE_ALIAS;

RE$TABLE_VALUE Type

Specifies the value of a table row using a ROWID.

Syntax

TYPE SYS.RE$TABLE_VALUE(
   table_alias       VARCHAR2(32), 
   table_rowid       VARCHAR2(18)); 

Attributes

Table 109-11 RE$TABLE_VALUE Attributes

Attribute	Description
table_alias	Specifies the alias used for the table in a rule
table_rowid	Specifies the rowid for the table row

RE$TABLE_VALUE_LIST Type

Identifies a list of table values used in a rule evaluation context.

Syntax

TYPE SYS.RE$TABLE_VALUE_LIST AS VARRAY(1024) OF SYS.RE$TABLE_VALUE;

RE$VARIABLE_TYPE Type

Provides the type of a variable used in a rule evaluation context. A specified variable name must satisfy the schema object naming rules.

See Also: Oracle9i SQL Reference for information about schema object naming rules

Syntax

TYPE SYS.RE$VARIABLE_TYPE (
   variable_name             VARCHAR2(32),
   variable_type             VARCHAR2(4000),
   variable_value_function   VARCHAR2(228),
   variable_method_function  VARCHAR2(228));

Attributes

Table 109-12 RE$VARIABLE_TYPE Attributes

Attribute	Description
variable_name	The variable name used in a rule
variable_type	The type that is resolved in the evaluation context schema. Any valid Oracle built-in datatype, user-defined type, or Oracle-supplied type can be specified. See the Oracle9i SQL Reference for more information about these types.
variable_value_function	A value function that can be specified for implicit variables. A synonym can be specified. The function name is resolved in the evaluation context schema. See the "Usage Notes" for more information.
variable_method_function	Specifies a value function, which can return the result of a method invocation. Specifying such a function can speed up evaluation, if there are many simple rules that invoke the method on the variable. The function can be a synonym or a remote function. The function name is resolved in the evaluation context schema. It is executed on behalf of the owner of a rule set using the evaluation context or containing a rule that uses the evaluation context. See the "Usage Notes" for more information.

Usage Notes

The functions for both the for the variable_value_function parameter and variable_method_function parameter have the following format:

schema_name.package_name.function_name@dblink

For example, if the schema_name is hr, the package_name is var_pac, the function_name is func_value, and the dblink is dbs1.net, then enter the following:

hr.var_pac.func_value@dbs1.net

The following sections describe the signature of the functions.

Signature for variable_value_function

The function must have the following signature:

FUNCTION variable_value_func(
  evaluation_context_schema  IN VARCHAR2,       
  evaluation_context_name    IN VARCHAR2,
  variable_name              IN VARCHAR2,
  event_context              IN SYS.RE$NV_LIST )
RETURN SYS.RE$VARIABLE_VALUE;

Signature for variable_method_function

This function must have the following signature:

FUNCTION variable_method_function(    
  evaluation_context_schema  IN VARCHAR2, 
  evaluation_context_name    IN VARCHAR2, 
  variable_value             IN SYS.RE$VARIABLE_VALUE, 
  method_name                IN VARCHAR2, 
  event_context              IN SYS.RE$NV_LIST) 
RETURN SYS.RE$ATTRIBUTE_VALUE;

RE$VARIABLE_TYPE_LIST Type

Identifies a list of variables and their types used in a rule evaluation context.

Syntax

TYPE SYS.RE$VARIABLE_TYPE_LIST AS VARRAY(1024) OF SYS.RE$VARIABLE_TYPE;

RE$VARIABLE_VALUE Type

Specifies the value of a variable.

Syntax

TYPE SYS.RE$VARIABLE_VALUE (
   variable_name       VARCHAR2(32), 
   variable_data       SYS.AnyData); 

Attributes

Table 109-13 RE$VARIABLE_VALUE Attributes

Attribute	Description
variable_name	Specifies the variable name used in a rule
variable_data	Specifies the data for the variable value

RE$VARIABLE_VALUE_LIST Type

Identifies a list of variable values used in a rule evaluation context.

Syntax

TYPE SYS.RE$VARIABLE_VALUE_LIST AS VARRAY(1024) OF SYS.RE$VARIABLE_VALUE;