Oracle10g Expression Filter Object Type
The Expression Filter feature is supplied with a set of
predefined types and public synonyms for these types. Most of
these types are used for configuring index parameters with the
Expression Filter procedural APIs. The exf$table_alias type is
used to support expressions defined on one or more database
tables.
All the values and names passed to the types defined in this
chapter are case-insensitive. In order to preserve the case,
double quotation marks should be used around the values.
The next topic in this section on Expression Filters will
discuss the dbms_expfil package, the heart of the Expression
Filter feature.
The core of the Expression Filter feature is the dbms_expfil
package. This package contains the various procedures used to
manage the Expression datatype and Expression data. The following
table describes the procedures in the dbms_expfil package.
|
PROCEDURE |
DESCRIPTION |
|
add_elementary_attribute |
Adds a specified attribute to
the attribute set. |
|
add_functions |
Adds a Function, Type, or
Package to the approved list of objects within an attribute
set |
|
assign_attribute_set |
Assigns an attribute set to
the specified table column used for storing expressions. |
|
build_exception_table |
Creates an exception table to
hold references to invalid expressions. |
|
clear_exprset_stats |
Clears the predicate
statistics for an expression set. |
|
copy_attribute_set |
Makes a copy of the attribute
set. |
|
create_attribute_set |
Creates an attribute set. |
|
default_index_parameters |
Assigns default index
parameters to an attribute set. |
|
default_xpindex_parameters |
Assigns default XPath index
parameters to an attribute set. |
|
defrag_index |
Rebuilds the bitmap indexes
online to reduce fragmentation. |
|
drop_attribute_set |
Drops an unused attribute set. |
|
get_exprset_stats |
Collects predicate statistics
for an expression set. |
|
grant_privilege |
Grants an expression DML
privilege to a user. |
|
index_parameters |
Assigns index parameters to an
expression set. |
|
revoke_privilege |
Revokes an expression DML
privilege from a user. |
|
unassign_attribute_set |
Breaks the association between
a column storing expressions and the attribute set. |
|
validate_expressions |
Validates expression metadata
and the expressions stored in a column. |
|
xpindex_parameters |
Assigns XPath index parameters
to an expression set. |
Table 6.3 dbms_expfil Procedures We have mentioned several views associated with Expressions,
let's take a quick look at them as the final topic in this section |
