Oracle® Data Cartridge Developer's Guide 10g Release 1 (10.1) Part Number B10800-01 |
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This chapter describes Java language Oracle Data Cartridge Interface extensible indexing interfaces. This chapter contains these topics:
Caution: These routines are invoked by Oracle at the appropriate times based on SQL statements executed by the end user. Do not invoke these routines directly as this may result in corruption of index data. |
The ODCIGetInterfaces
function is invoked when an INDEXTYPE
is created by a CREATE
INDEXTYPE...
statement or is altered.
ODCIGetInterfaces( ifclist OUT ODCIObjectList) RETURN NUMBER
Table 20-1 ODCIGetInterfaces Arguments
Argument | Meaning |
---|---|
ifclist |
Contains information about the interfaces it supports |
ODCIConst.Success
on success
ODCIConst.Error
on error
This function should be implemented as a static type method.
This function must return SYS.ODCIINDEX2
in the ODCIObjectList
if the indextype uses the second version of the ODCIIndex
interface, which was implemented in the current version of the Oracle Database and is described in this book.
To continue to use the Oracle8i interface, make this function return SYS.ODCIINDEX1
and do not implement subsequent versions of the routines.
Invoked when a domain index or a domain index partition is altered using an ALTER INDEX
or an ALTER INDEX PARTITION
statement.
ODCIIndexAlter( ia ODCIIndexInfo, parms IN OUT VARCHAR2, alter_option NUMBER, env ODCIEnv) RETURN NUMBER
Table 20-2 ODCIIndexAlter Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the index and the indexed column |
parms (IN) |
Parameter string
With With |
parms (OUT) |
Parameter string
Valid only with |
alter_option |
Specifies one of the following options:
|
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, ODCIConst.Error
on error, or ODCIConst.Warning
otherwise.
This function should be implemented as a static type method.
An ALTER
INDEX
statement can be invoked for domain indexes in multiple ways.
ALTER INDEX index_name PARAMETERS (parms);
or
ALTER INDEX index_name REBUILD PARAMETERS (parms);
The precise behavior in these two cases is defined by the implementor. One possibility is that the first statement would merely reorganize the index based on the parameters while the second would rebuild it from scratch.
The maximum length of the input parameters string is 1000 characters. The OUT
value of the parms
argument can be set to resultant parameters string to be stored in the system catalogs.
The ALTER
INDEX
statement can also be used to rename a domain index in the following way:
ALTER INDEX index_name RENAME TO new_index_name
In this case, the new name of the domain index is passed to the parms
argument.
If the PARALLEL
clause is omitted, then the domain index or local domain index partition is rebuilt sequentially.
If the PARALLEL
clause is specified, the parallel degree is passed to the ODCIIndexAlter
invocation in the IndexParaDegree
attribute of ODCIIndexInfo
, and the Parallel
bit of the IndexInfoFlags
attribute is set. The parallel degree is determined as follows:
If PARALLEL DEGREE
deg is specified, deg is passed.
If only PARALLEL
is specified, then a constant is passed to indicate that the default degree of parallelism was specified.
If the ODCIIndexAlter
routine returns with the ODCIConst
.Success
, the index is valid and usable. If the ODCIIndexAlter
routine returns with ODCIConst
.Warning
, the index is valid and usable but a warning message is returned to the user. If ODCIIndexAlter
returns with an error (or exception), the domain index will be marked FAILED
.
When the ODCIIndexAlter
routine is being executed, the domain index is marked LOADING
.
Every SQL statement executed by ODCIIndexAlter is treated as an independent operation. The changes made by ODCIIndexCreate are not guaranteed to be atomic.
The AlterIndexUpdBlockRefs
alter option applies only to domain indexes on index-organized tables. When the end user executes an ALTER INDEX
<domain_index> UPDATE BLOCK REFERENCES
, ODCIIndexAlter
is called with the AlterIndexUpdBlockRefs
bit set to give the cartridge developer the opportunity to update guesses as to the block locations of rows, stored in logical rowids.
Invoked to end the processing of an operator.
ODCIIndexClose( self IN <impltype>, env ODCIEnv) RETURN NUMBER
Table 20-3 ODCIIndexClose Arguments
Argument | Meaning |
---|---|
self(IN) |
Is the value of the context returned by the previous invocation of ODCIIndexFetch |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success
ODCIConst.Error
on error
The index implementor can perform any appropriate actions to finish up the processing of an domain index scan, such as freeing memory and other resources.
Invoked when a domain index is created by a CREATE INDEX...INDEXTYPE IS...PARAMETERS...
statement issued by the user. The domain index that is created can be a non-partitioned index or a local partitioned domain index.
ODCIIndexCreate( ia ODCIIndexInfo, parms VARCHAR2, env ODCIEnv) RETURN NUMBER
Table 20-4 ODCIIndexCreate Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the indexed column |
parms |
Is the PARAMETERS string passed in uninterpreted by Oracle. The maximum size of the parameter string is 1000 characters. |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success
ODCIConst.Error
on error
ODCIConst.Warning
ODCIConst.ErrContinue
if the method is invoked at the partition level for creation of a local partitioned index, to continue to the next partition even in case of an error
ODCIConst.Fatal
to signify that all dictionary entries for the index are cleaned up and that the CREATE INDEX
operation is rolled back. Returning this status code assumes that the cartridge code has not created any objects (or cleaned up any objects created).
This function should be implemented as a static type method.
The ODCIIndexCreate
routine should create objects (such as tables) to store the index data, generate the index data, and store the data in the index data tables.
The ODCIIndexCreate
procedure should handle creation of indexes on both empty and non-empty tables. If the base table is not empty, the ODCIIndexCreate
procedure can scan the entire table and generate index data.
Every SQL statement executed by ODCIIndexCreate
is treated as an independent operation. The changes made by ODCIIndexCreate
are not guaranteed to be atomic.
For a non-partitioned domain index, the parallel degree is passed to the ODCIIndexCreate
invocation in the IndexParaDegree
attribute of ODCIIndexInfo
, and the Parallel
bit of the IndexInfoFlags
is set. The parallel degree is determined as follows:
If PARALLEL DEGREE
deg specified, deg is passed.
If only PARALLEL
is specified, then a constant indicating that the default degree of parallelism was specified, is passed.
If the PARALLEL
clause is omitted altogether, the operation is done sequentially
When the ODCIIndexCreate
routine is being executed, the domain index is marked LOADING
.
If the ODCIIndexCreate
routine returns with the ODCIConst
.Success
, the index is valid and usable. If the ODCIIndexCreate
routine returns with ODCIConst
.Warning
, the index is valid and usable but a warning message is returned to the user. If the ODCIIndexCreate
routine returns with an ODCIConst
.Error
(or exception), the domain index will be marked FAILED.
The only operations permitted on FAILED
domain indexes is DROP
INDEX
, TRUNCATE
TABLE
or ALTER
INDEX
REBUILD
.
If a domain index is created on an column of object type which contains a REF
attribute, do not dereference the REF
s while building your index. Dereferencing a REF
fetches data from a different table instance. If the data in the other table is modified, you will not be notified and your domain index will become incorrect.
To create a non-partitioned domain index, the ODCIIndexCreate
method is invoked once, and the only valid return codes are ODCIConstSuccess
, ODCIConstWarning
or ODCIConstError
. The IndexPartition
and TablePartition
name are NULL
and callProperty
is also NULL
.
To create a local partitioned domain index, the ODCIIndexCreate
method is invoked n+2
times, where n is the number of local index partitions. The first and the final call handle operations on the top-level index object, and the intermediate n calls handle partition-level objects. In the first call, a table to hold the index level metadata can be created. In the intermediate calls, independent tables to hold partition level data can be created and populated, and in the last call, indexes can be built on the index metadata tables and so forth.
For local partitioned domain indexes, the first and the last call can return ODCIConstSuccess
, ODCIConstWarning
or ODCIConstError
. The intermediate N calls can return ODCIConstSuccess
, ODCIConstWarning
, ODCIConstError
or ODCIConstErrContiue
. If a partition level call returns ODCIConstError
, the partition is marked FAILED
, the index is marked FAILED
, and the create operation terminates at that point. If the call returns ODCIConstErrContinue
, the partition is marked FAILED
, and the method is invoked for the next partition.
This method is invoked during ALTER TABLE ADD PARTITION
too. In this case, there is only one call to ODCIIndexCreate
, the IndexPartition
and TablePartition
name are filled in, and the callProperty
is set to NULL
Since this routine handles multiple things (namely, creation of a non-partitioned index, creation of a local index and creation of a single index partition), you must take special care to code it appropriately.
Invoked when a row is deleted from a table that has a domain index defined on one or more of its columns.
ODCIIndexDelete( ia ODCIIndexInfo, rid VARCHAR2, oldval <icoltype>, env ODCIEnv) RETURN NUMBER
Table 20-5 ODCIIndexDelete Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the index and the indexed column |
rid |
The row identifier of the deleted row |
oldval |
The value of the indexed column in the deleted row. The datatype is the same as that of the indexed column. |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error
This function should be implemented as a static type method.
This method should delete index data corresponding to the deleted row from the appropriate tables or files storing index data.
If ODCIIndexDelete
is invoked at the partition level, then the index partition name is filled in the ODCIIndexInfo
argument.
The ODCIIndexDrop
procedure is invoked when a domain index is dropped explicitly using a DROP
INDEX
statement, or implicitly through a DROP
TABLE
, or DROP
USER
statement.
ODCIIndexDrop( ia ODCIIndexInfo, env ODCIEnv) RETURN NUMBER
Table 20-6 ODCIIndexDrop Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the indexed column |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error, or ODCIConst.Warning
While dropping a local domain index, the first n+1
calls can return ODCIConst.ErrContinue
too.
This method should be implemented as a static type method.
This method should drop the tables storing the domain index data.
This method is invoked for dropping a non-partitioned index, dropping a local domain index, and also for dropping a single index partition during ALTER TABLE DROP PARTITION
.
For dropping a non-partitioned index, the ODCIIndexDrop
is invoked once, with the IndexPartition
, TablePartition
and callProperty
set to NULL
.
For dropping a local domain index, the routine is invoked N+2 times, where N is the number of partitions.
For dropping a single index partition during ALTER TABLE DROP PARTITION
, this routine is invoked once with the IndexPartition
and the TablePartition
filled in and the callProperty
set to NULL
.
The old table and the old index partition's dictionary entries are deleted before the call to ODCIIndexDrop
, so the cartridge code for this routine should not rely on the existence of this data in the views.
Since it is possible that the domain index is marked FAILED
(due to abnormal termination of some DDL routine), the ODCIIndexDrop
routine should be capable of cleaning up partially created domain indexes. When the ODCIIndexDrop
routine is being executed, the domain index is marked LOADING
.
Note that if the ODCIIndexDrop
routine returns with an ODCIConst.Error
or exception, the DROP
INDEX
statement fails and the index is marked FAILED
. In that case, there is no mechanism to get rid of the domain index except by using the FORCE
option. If the ODCIIndexDrop
routine returns with ODCIConst
.Warning
in the case of an explicit DROP
INDEX
statement, the operation succeeds but a warning message is returned to the user.
Every SQL statement executed by ODCIIndexDrop
is treated as an independent operation. The changes made by ODCIIndexDrop
are not guaranteed to be atomic.
This method is invoked when an ALTER TABLE EXCHANGE PARTITION...INCLUDING INDEXES
is issued on a partitioned table on which a local domain index is defined.
ODCIIndexExchangePartition( ia ODCIIndexInfo, ia1 ODCIIndexInfo, env ODCIEnv) RETURN NUMBER
Table 20-7 ODCIIndexExchangePartition Arguments
Argument | Meaning |
---|---|
ia | Contains information about the partition to exchange |
ia1 | Contains information about the non-local, unpartitioned domain index |
env | The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error, or ODCIConst.Warning
The function should be implemented as a static type method.
This method should handle both converting a partition of a domain index into a non-partitioned domain index table and converting a non-partitioned index to a partition of a partitioned domain index.
This procedure is invoked repeatedly to retrieve the rows satisfying the operator predicate.
ODCIIndexFetch( self IN [OUT] <impltype>, nrows IN NUMBER, rids OUT ODCIRidList, env ODCIEnv) RETURN NUMBER
Table 20-8 ODCIIndexFetch Arguments
Argument | Meaning |
---|---|
self(IN) |
Is the value of the context returned by the previous call (to ODCIIndexFetch or to ODCIIndexStart if this is the first time fetch is being called for this operator instance |
self(OUT) |
The context that is passed to the next query-time call. Note that this parameter does not have to be defined as OUT if the value is not modified in this routine. |
nrows |
Is the maximum number of result rows that can be returned to Oracle in this call |
rids |
Is the array of row identifiers for the result rows being returned by this call |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error
ODCIIndexFetch
returns rows satisfying the operator predicate. That is, it returns the row identifiers of all the rows for which the operator return value falls within the specified bounds.
Each call to ODCIIndexFetch
can return a maximum of nrows number of rows. The value of nrows passed in is decided by Oracle based on some internal factors. However, the ODCIIndexFetch
routine can return lesser than nrows number of rows. The row identifiers are returned through the output rids
array. A NULL
ROWID
(as an element of the rids
array) indicates that all satisfying rows have been returned.
Assume that there are 3000 rows which satisfy the operator predicate, and that the value of nrows
= 2000. The first invocation of ODCIIndexFetch
can return the first 2000 rows. The second invocation can return a rid
list consisting of the remaining 1000 rows followed by a NULL
element. The NULL
value in rid
list indicates that all satisfying rows have now been returned.
If the context value is changed within this call, the new value is passed in to subsequent query-time calls.
Returns a series of strings of PL/SQL code that comprise the non-dictionary metadata associated with the index in ia
. The routine can pass whatever information is required at import time—for example, policy, version, preferences, and so on. This method is optional unless implementation-specific metadata is required.
ODCIIndexGetMetadata( ia IN ODCIIndexInfo, version IN VARCHAR2, new_block OUT PLS_INTEGER) RETURN VARCHAR2;
Table 20-9 ODCIIndexGetMetadata Arguments
Argument | Description |
---|---|
ia |
Specifies the index on which export is currently working. |
version |
Version of export making the call in the form 08.01.03.00.00 . |
new_block |
Non-zero (TRUE ): Returned string starts a new PL/SQL block. Export will terminate the current block (if any) with END ; and open a new block with BEGIN before writing strings to the dump file. The routine is called again.
|
Developers of domain index implementation types in 8.1.3 must implement ODCIIndexGetMetadata
even if only to indicate that no PL/SQL metadata exists or that the index is not participating in fast rebuild.
A null-terminated string containing a piece of an opaque block of PL/SQL code
A zero-length string indicates no more data; export stops calling the routine
This function should be implemented as a static type method.
The routine will be called repeatedly until the return string length is 0. If an index has no metadata to be exported using PL/SQL, it should return an empty string upon first call.
This routine can be used to build one or more blocks of anonymous PL/SQL code for execution by import. Each block returned will be invoked independently by import. That is, if a block fails for any reason at import time, subsequent blocks will still be invoked. Therefore any dependent code should be incorporated within a single block. The size of an individual block of PL/SQL code is limited only by the size of import's read buffer controlled by its BUFFER
parameter.
The execution of these PL/SQL blocks at import time will be considered part of the associated domain index's creation. Therefore, their execution will be dependent upon the successful import of the index's underlying base table and user's setting of import's INDEXES=Y/N
parameter, as is the creation of the index.
The routine should not pass back the BEGIN
/END
strings that open and close the individual blocks of PL/SQL code; export will add these to mark the individual units of execution.
The parameter version
is the version number of the currently executing export client. Since export and import can be used to downgrade a database to the previous functional point release, it also represents the minimum server version you can expect to find at import time; it may be higher, but never lower.
The cartridge developer can use this information to determine what version of information should be written to the dump file. For example, assume the current server version is 08.02.00.00.00
, but the export version handed in is 08.01.04.00.00
. If a cartridge's metadata changed formats between 8.1 and 8.2, it would know to write the data to the dump file in 8.1 format anticipating an import into an 8.1.4 system. Server versions starting at 8.2 and higher will have to know how to convert 8.1 format metadata.
The data contained within the strings handed back to export must be completely platform-independent. That is, they should contain no binary information that may reflect the endian nature of the export platform, which may be different from the import platform. Binary information may be passed as hex strings and converted through RAWTOHEX
and HEXTORAW
.
The strings are translated from the export server to export client character set and are written to the dump file as such. At import time, they are translated from export client character set to import client character set, then from import client char set to import server character set when handed over the UPI interface.
Specifying a specific target schema in the execution of any of the PL/SQL blocks should be avoided as it will most likely cause an error if you exercise import's FROMUSER
-> TOUSER
schema replication feature. For example, a procedure prototype such as:
PROCEDURE AQ_CREATE ( schema IN VARCHAR2, que_name IN VARCHAR2) ...
should be avoided since this will fail if you have remapped schema A to schema B on import. You can assume at import time that you are already connected to the target schema.
Export dump files from a particular version must be importable into all future versions. This means that all PL/SQL routines invoked within the anonymous PL/SQL blocks written to the dump file must be supported for all time. You may wish to encode some version information to assist with detecting when conversion may be required.
Export will be operating in a read-only transaction if its parameter CONSISTENT=Y
. In this case, no writes are allowed from the export session. Therefore, this method must not write any database state.
You can attempt to import the same dump file multiple times, especially when using import's IGNORE=Y
parameter. Therefore, this method must produce PL/SQL code that is idempotent, or at least deterministic when executed multiple times.
Case on database object names must be preserved; that is, objects named 'Foo
' and 'FOO
' are distinct objects. Database object names should be enclosed within double quotes ("") to preserve case.
Any unrecoverable error should raise an exception allowing it to propagate back to get_domain_index_metadata
and thence back to export. This will cause export to terminate the creation of the current index's DDL in the dump file and to move on to the next index.
At import time, failure of the execution of any metadata PL/SQL block will cause the associated index not to be created under the assumption that the metadata creation is an integral part of the index creation.
Invoked when a row or a set of rows is inserted into a table that has a domain index defined on one or more of its columns.
Table 20-10 ODCIIndexInsert Versions
Argument | Meaning |
---|---|
ODCIIndexInsert( ia ODCIIndexInfo, rid VARCHAR2, newval <icoltype>, env ODCIEnv) RETURN NUMBER |
Inserts a single row |
ODCIIndexInsert( ia ODCIIndexInfo, ridlist ODCIRidList, newvallist <varray of column type>, env ODCIEnv) RETURN NUMBER |
inserts a set of rows |
Table 20-11 ODCIIndexInsert Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the index and the indexed column |
rid |
The row identifier of the new row in the table |
newval |
The value of the indexed column in the inserted row |
ridlist |
A varray (maximum size 32767) containing the list of rowids for the rows being inserted into the base table |
newvallist |
A varray (maximum size 32767) containing the list of values being inserted into the indexed column in the base table; these entries have a one-to-one correspondence with the entries in ridlist |
env |
The environment handle passed to the routine |
ODCIConst
.Success
on success, or ODCIConst.Error
on error
This function should be implemented as a static type method.
This method should insert index data corresponding to the row or set of rows passed in into the appropriate tables or files storing index data. A NULL value in ridlist
indicates the end of the varray.
If the indextype is defined WITH ARRAY DML
, a batch of rows can be inserted into the table. In this case, ODCIIndexInsert
is invoked using the second of the two syntax synopses. Otherwise, the single-row syntax is used.
If ODCIIndexInsert
is invoked at the partition level, then the index partition name is filled in the ODCIIndexInfo
argument.
Invoked when a ALTER TABLE MERGE PARTITION
is issued on range partitioned table on which a local domain index is defined.
ODCIIndexMergePartition( ia ODCIIndexInfo, part_name1 ODCIPartInfo, part_name2 ODCIPartInfo, parms VARCHAR2, env ODCIEnv) RETURN NUMBER
Table 20-12 ODCIIndexMergePartition Arguments
Argument | Meaning |
---|---|
ia |
Contains index and table partition name for one of the partitions to be merged |
part_name1 |
Contains index and table partition name for the second partition to be merged |
part_name2 |
Holds index and table partition name for the merged partition |
parms |
Contains the parameter string for the resultant merged partition, essentially the default parameter string associated with the index |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error, or ODCIConst.Warning
.
The function should be implemented as a static type method.
You should create a new table representing the resultant merged partition and populate it with data from the merged partitions. Then drop the tables corresponding to the merged index partitions. Also, the newly created partition should pick the default parameter string associated with the index level.
The old table and the old index partitions' dictionary entries are deleted before the call to ODCIIndexMergePartition
, so the cartridge code for this routine should not rely on the existence of this data in the views.
Invoked when an ALTER TABLE SPLIT PARTITION
is invoked on a partitioned table on which a local domain index is defined.
ODCIIndexSplitPartition( ia ODCIIndexInfo, part_name1 ODCIPartInfo, part_name2 ODCIPartInfo, parms VARCHAR2, env ODCIEnv) RETURN NUMBER
Table 20-13 ODCIIndexSplitPartition Arguments
Argument | Meaning |
---|---|
ia |
Contains the information about the partition to be split |
part_name1 |
Holds the index and table partition names for one of the new partitions |
part_name2 |
Holds the index and table partition names for the other new partition |
parms |
Contains the parameter string for the new partitions— essentially the parameter string associated with the index partition that is being split |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error, or ODCIConst.Warning
.
The function should be implemented as a static type method.
Cartridge writers need to drop the metadata corresponding to the partition that is split and create metadata for the two partitions that are created as a result of the split. The index data corresponding to these partitions need not be computed since the indexes are marked UNUSABLE
. When the user issues ALTER INDEX REBUILD PARTITION
to make the indexes usable, the indexes can be built.
The old table and the old index partition's dictionary entries are deleted before the call to ODCIIndexSplitPartition
, so the cartridge code for this routine should not rely on the existence of this data in the views.
Invoked to start the evaluation of an operator on an indexed column.
ODCIIndexStart( sctx IN OUT <impltype>, ia ODCIIndexInfo, pi ODCIPredInfo, qi ODCIQueryInfo, strt <opbndtype>, stop <opbndtype>, <valargs>, env ODCIEnv) RETURN NUMBER
Table 20-14 ODCIIndexStart Arguments
Argument | Meaning |
---|---|
sctx(IN) |
The value of the scan context returned by some previous related query-time call (such as the corresponding ancillary operator, if invoked before the primary operator); NULL otherwise |
sctx(OUT) |
The context that is passed to the next query-time call; the next query-time call will be to ODCIIndexFetch |
ia |
Contains information about the index and the indexed column |
pi |
Contains information about the operator predicate |
qi |
Contains query information (hints plus list of ancillary operators referenced) |
strt |
The start value of the bounds on the operator return value. The datatype is the same as that of the operator's return value |
stop |
The stop value of the bounds on the operator return value. The datatype is the same as that of the operator's return value. |
valargs |
The value arguments of the operator invocation. The number and datatypes of these arguments are the same as those of the value arguments to the operator. |
env |
The environment handle passed to the routine |
ODCIConst
.Success
on success, or ODCIConst.Error
on error
The function should be implemented as a static method.
ODCIIndexStart
is invoked to begin the evaluation of an operator on an indexed column. In particular, the following conditions hold:
The first argument to the operator is a column which has a domain index defined on it.
The indextype of the domain index (specified in ODCIIndexInfo
parameter) supports the current operator.
All other arguments to the operator are value arguments (literals) which are passed in through the <valargs>
parameters.
The ODCIIndexStart
method should initialize the index scan as needed (using the operator-related information in the pi
argument) and prepare for the subsequent invocations of ODCIIndexFetch
.
The strt
, stop
parameters together with the bndflg
value in ODCIPredInfo
parameter specify the range of values within which the operator return value should lie.
Bounds for operator return values are specified as follows:
If the predicate to be evaluated is of the form op
LIKE
val
, the ODCIIndexPrefixMatch
flag is set. In this case, the start key contains the value <val>
and the stop key value is irrelevant.
If the predicate to be evaluated is of the form op
= val
, the ODCIIndexExactMatch
flag is set. In this case, the start key contains the value <val>
and the stop key value is irrelevant.
If the predicate to be evaluated is of the form op
> val
, startkey
contains the value <val>
and stop key value is set to NULL
. If the predicate is of the form op
>= <val>
, the flag ODCIIndexIncludeStart
is also set.
If the predicate to be evaluated is of the form op
< val
, stop key contains the value <val> and the start key value is set to NULL
. If the predicate is of the form op
<= val
, the flag ODCIIndexIncludeStop
is also set.
A context value can be returned to Oracle (through the SELF
argument) which will then be passed back to the next query-time call. The next call will be to ODCIIndexFetch
if the evaluation continues, or to ODCIIndexStart
if the evaluation is restarted. The context value can be used to store the entire evaluation state or just a handle to the memory containing the state.
Note that if the same indextype supports multiple operators with different signatures, multiple ODCIIndexStart
methods need to be implemented, one for each distinct combination of value argument datatypes. For example, if an indextype supports three operators:
op1(number, number)
op1(varchar2, varchar2)
op2(number, number)
two ODCIIndexStart
routines would need to be implemented:
ODCIIndexStart(...., NUMBER)
— handles cases (1) and (3) which has a NUMBER
value argument
ODCIIndexStart(...., VARCHAR2)
— handles case (2) which has a VARCHAR2
value argument
The query information in qi
parameter can be used to optimize the domain index scan, if possible. The query information includes hints that have been specified for the query and the list of relevant ancillary operators referenced in the query block.
Invoked when a TRUNCATE
statement is issued against a table that has a domain index defined on one of its columns.
ODCIIndexTruncate( ia ODCIIndexInfo, env ODCIEnv) RETURN NUMBER
Table 20-15 ODCIIndexTruncate Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the indexed column |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error, or ODCIConst.Warning
.
While truncating a local domain index, the first N+1 calls can return ODCIConst.ErrContinue
too.
This function should be implemented as a static type method.
After this function executes, the domain index should be empty (corresponding to the empty base table).
While the ODCIIndexTruncate
routine is being executed, the domain index is marked LOADING
. If the ODCIIndexTruncate
routine returns with an ODCIConst
.Error
(or exception), the domain index will be marked FAILED
. The only operation permitted on FAILED
domain indexes is DROP
INDEX
, TRUNCATE
TABLE
or ALTER
INDEX
REBUILD
. If ODCIIndexTruncate
returns with ODCIConst
.Warning
, the operation succeeds but a warning message is returned to the user.
Every SQL statement executed by ODCIIndexTruncate
is treated as an independent operation. The changes made by ODCIIndexTruncate
are not guaranteed to be atomic.
This method is invoked for truncating a non-partitioned index, truncating a local domain index, and also for truncating a single index partition during ALTER TABLE TRUNCATE PARTITION
.
For truncating a non-partitioned index, the ODCIIndexTruncateis
invoked once, with the IndexPartition
, TablePartition
and callProperty
set to NULL
.
For truncating a local domain index, the routine is invoked N+2 times, where N is the number of partitions.
For truncating a single index partition during ALTER TABLE TRUNCATE PARTITION
, this routine is invoked once with the IndexPartition
and the TablePartition
filled in and the callProperty
set to NULL
.
Invoked when a row is updated in a table and the updated column has a domain index defined on it.
ODCIIndexUpdate( ia ODCIIndexInfo, rid VARCHAR2, oldval <icoltype>, newval <icoltype>, env ODCIEnv) RETURN NUMBER
Table 20-16 ODCIIndexUpdate Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the index and the indexed column |
rid |
The row identifier of the updated row |
oldval |
The value of the indexed column before the update. The datatype is the same as that of the indexed column. |
newval |
The value of the indexed column after the update. The datatype is the same as that of the indexed column. |
env |
The environment handle passed to the routine |
ODCIConst.Success
on success, or ODCIConst.Error
on error
The function should be implemented as a static type method.
This method should update the tables or files storing the index data for the updated row.
In addition to a SQL UPDATE
statement, a LOB value can be updated through a variety of WRITE
interfaces (see Oracle Database Application Developer's Guide - Large Objects). If a domain index is defined on a LOB
column or an object type containing a LOB
attribute, the ODCIIndexUpdate
routine is called when a LOB locator is implicitly or explicitly closed after one or more write operations.
If ODCIIndexUpdate
is invoked at the partition level, then the index partition name is filled in the ODCIIndexInfo
argument.
Implemented only if you want to have transportable tablespace support for domain indexes defined using this indextype. It is invoked during a transportable tablespace session to cleanup any temporary state created by ODCIIndexUtilGetTableNames
.
ODCIIndexUtilCleanup ( context PLS_INTEGER)
Table 20-17 ODCIIndexUtilCleanup Arguments
Argument | Meaning |
---|---|
context |
The number created by ODCIIndexGetTableNames that uniquely identifies state information for a particular index. |
The procedure should be implemented as a static type method.
ODCIIndexUtilCleanup
deletes any temporary state associated with the parameter context.
Exceptions raised by ODCIIndexUtilCleanup
will be ignored by its caller.
This method needs to be implemented only if you want to have transportable tablespace support for domain indexes defined using this indextype. It is invoked during a transportable tablespace session to determine if the secondary tables storing the index data should be transported.
ODCIIndexUtilGetTableNames( ia sys.odciindexinfo, read_only PLS_INTEGER, version varchar2, context OUT PLS_INTEGER) RETURN BOOLEAN
Table 20-18 ODCIIndexUtilGetTableNames Arguments
Argument | Meaning |
---|---|
ia |
Contains information about the index and the indexed column |
read_only |
Specify 1 if the encompassing transaction is read-only, meaning no writes allowed. Otherwise 0. |
version |
Version of export making the call. |
context |
A unique number that is used by ODCIIndexUtilCleanup to facilitate the clean up of any state held open between ODCIIndexUtilGetTableNames and ODCIIndexCleanup . |
TRUE if the domain indexes' secondary tables should be transported. Otherwise, the function returns FALSE.
This function should be implemented as a static type method.
This function should return TRUE or FALSE based on whether the secondary tables should be transported or not. Secondary objects other than tables do not participate in transportable tablespaces. They will need to be recreated on the import side when the ODCIIndexCreate
method is invoked with the ODCI_INDEX_TRANS_TBLSPC
bit set in the ODCIIndexInfo.IndexInfoFlags
.