Spatial Engine OracleSpatial

A spatial engine provides access to a service that can perform spatial operations, one of the available spatial engines is for Oracle Spatial.

ESRI GeoDatabase enabled Oracle databases are currently not supported by Weave as a spatial engine. If access is required it will have to be via ArcGis server.

Namespace

urn:com.cohga.server.spatial.geotools#1.0

Tags

spatialengine

Properties

Name	Type	Required	Description
id	string	yes	Unique identifier
dbtype	'oracle'	yes	The name of the driver to use, in this case Oracle
host	string	yes	The hostname or ip address of the Oracle server
port	number	yes	The port number that the Oracle instance is running on
database	string	no	The database parameter for the connection url
username	string	yes	The userid used when connecting to the database
password	string	yes	The password used when connecting to the database
schema	string	no	The schema used when connecting to the database
minconnections	integer	no	The minimum number of pooled connection. Default 1
maxconnections	integer	no	The maximum number of open connections. Default 10
maxopenpreparedstatements	integer	no	Set the maximum number of prepared statements, -1 to disable prepared statement caching.
validateconnections	boolean	no	Check connection is alive before using it. Default false
fetchsize	integer	no	The number of records read with each iteraction with the dbms. Default 1000
connectiontimeout	integer	no	The number of seconds the connection pool will wait before timing out attempting to get a new connection. Default 20 (seconds)
primarykeymetadatatable	string	no	The optional table containing primary key structure and sequence associations. Can be expressed as 'schema.name' or just 'name'. Default none
maxopenpreparedstatements	integer	no	Maximum number of prepared statements kept open and cached for each connection in the pool. Set to 0 to have unbounded caching, to -1 to disable caching. Default 50
geometrymetadatatable	string	no	The optional table containing metadata about the geometry for the tables being accessed via this spatial engine.

Sub-tags

None

Content

None

Notes

No connection pool configuration is provided with this driver, the driver manages the connection pooling itself.
If database starts with '(' then the format of the connection url will be
jdbc:oracle:thin:@database
If database starts with '/' then the format of the connection url will be
jdbc:oracle:thin:@//host:portdatabase
else the format of the connection url will be
jdbc:oracle:thin:@host:port:database

Examples

Basic Oracle connection

<spatial:spatialengine id="oracle">
	<dbtype>oracle</dbtype>
	<host>oradev</host>
	<port>1521</port>
	<user>gis</user>
	<passwd>hak0rz</passwd>
	<schema>GIS</schema>
</spatial:spatialengine>

Basic Oracle connection with the password using the osgi encrypt command and a database specified

<spatial:spatialengine id="sdbeos">
	<dbtype>oracle</dbtype>
	<host>sdbeos</host>
	<port>1521</port>
	<database>staging</database>
	<user>data_viewer</user>
	<passwd>ENCSSJKXUMJBMTPGEJFGCXCQFXJJZUTMJZJ</passwd>
	<schema>ASSETS</schema>
</spatial:spatialengine>

Primary Key Metadata

If the primary key for a table can not be determined by Weave directly from the database then the information can be provided by creating a table or directly embedding the information in the spatial engine configuration.

SQL create statement for gt_pk_metadata table

CREATE TABLE gt_pk_metadata (
  table_schema VARCHAR(32),
  table_name VARCHAR(32) NOT NULL,
  pk_column VARCHAR(32) NOT NULL,
  pk_column_idx INTEGER,
  pk_policy VARCHAR(32),
  pk_sequence VARCHAR(64),
  unique (table_schema, table_name, pk_column),
  check (pk_policy in ('sequence', 'assigned', 'autogenerated'))
)

pk_policy can be 'assigned', 'sequence' or 'autogenerated' depending upon how the key column value is generated. The pk_sequence value only need to be set if the policy is 'sequence'.
'sequence' means that the value for the column is generated using a database sequence, and the 'pk_sequence' value must be set.
'autogenerated' means that the value for the column is generated by the database using another method.
'assigned' means that the value for the column is determined by the current maximum value +1, if the column is an integral type, or as a random string if the column is textual.

Column	Description

Column	Description
table_schema	Name of the database schema in which the table is located.
table_name	Name of the table to be published
pk_column	Name of a column used to form the feature IDs
pk_column_idx	Index of the column in a multi-column key. In case multi column keys are needed multiple records with the same table schema and table name will be used.
pk_policy	The new value generation policy, used in case a new feature needs to be added in the table ('assigned', 'sequence' or 'autogenerated').
pk_sequence	The name of the database sequence to be used when generating a new value for the pk_column.

Using primary key metadata configuration

You can also specify the above information directly in the spatial engin configuration.

Name	Description

Name	Description
name	^{The table name}
schema	^{The optional table schema}
column	`The column in the the table that contains the unique id`
policy	`How the key is generated`
sequence	`The name of the database sequence to use if the policy is 'sequence'`

Geometry metadata

The Oracle data store will, by default, look into the MDSYS.USER_SDO* and MDSYS.ALL_SDO* views to determine the geometry type and native SRID of each geometry column. Those views are automatically populated with information about the geometry columns stored in tables that the current user owns (for the MDSYS.USER_SDO* views) or can otherwise access (for the MDSYS.ALL_SDO* views).

There are a few hiccups in this process:

• if the connection pool user cannot access the tables (because impersonation is being used) the MDSYS views will be empty, making it impossible to determine either the geometry type and the native SRID
• the geometry type can be specified only while building the spatial indexes, as a index constraint, however such information is often not included when creating the indexes
• the views are populated dynamically based on the current user, if the database has thousands of tables and users the views can become very slow

The database administrator can address the above issues by manually creating a geometry metadata table describing each geometry column, and then indicate its presence among the Oracle data store connection parameter named geometrymetadatatable (either as a simple table name, or a schema qualified one). The table has the following structure (the table name is free, just indicate the one chosen in the data store connection parameter):

When the table is present the store will first search it for information about each geometry column to be classified, and fall back on the MDSYS views only if such table does not contain any information.

Using geometry metadata configuration

As of Weave 2.5.16 it's possible to specify the information contained in the geometry metadata table directly in the spatial engine configuration.

Name	Description

Name	Description
name	The table name
schema	The optional table schema
type	The geometry type (point, linestring, curve, polygon, multipoint, multilinestring, multicurve, multipolygon)
srid	The geometry srid
dimension	The geometry dimension