SQL-functions
Functions in the sqlj schema
install_jar
The install_jar command loads a jarfile from a location appointed by an URL
into the SQLJ jar repository. It is an error if a jar with the given name
already exists in the repository.
Usage
SELECT sqlj.install_jar(<jar_url>, <jar_name>, <deploy>);
| Parameter | Description |
|---|---|
| jar_url | The URL that denotes the location of the jar that should be loaded |
| jar_name | This is the name by which this jar can be referenced once it has been loaded |
| deploy | True if the jar should be deployed according to a deployment descriptor, false otherwise |
replace_jar
The replace_jar command will replace a loaded jar with another jar.
Use it to update already loaded files. It’s an error if the jar is not found.
Usage
SELECT sqlj.replace_jar(<jar_url>, <jar_name>, <redeploy>);
| Parameter | Description |
|---|---|
| jar_url | The URL that denotes the location of the jar that should be loaded. |
| jar_name | The name of the jar to be replaced. |
| redeploy | True if the jar should be undeployed according to the deployment descriptor of the old jar and deployed according to the deployment descriptor of the new jar, false otherwise. |
remove_jar
The remove_jar command will drop the jar from the jar repository.
Any classpath that references this jar will be updated accordingly. It’s an
error if the jar is not found.
Usage
SELECT sqlj.remove_jar(<jar_name>, <undeploy>);
| Parameter | Description |
|---|---|
| jar_name | The name of the jar to be removed. |
| undeploy | True if the jar should be undeployed according to a deployment descriptor, false otherwise. |
get_classpath
The get_classpath command will return the classpath that has been defined for
the given schema. NULL is returned if the schema has no classpath. It’s an
error if the given schema does not exist.
Usage
SELECT sqlj.get_classpath(<schema>);
| Parameter | Description |
|---|---|
| schema | The name of the schema |
set_classpath
The set_classpath command will define a classpath for the given schema. A
classpath consists of a colon separated list of jar names. It’s an error if the
given schema does not exist or if one or more jar names references nonexistent
jars.
Usage
SELECT sqlj.set_classpath(<schema>, <classpath>);
| Parameter | Description |
|---|---|
| schema | The name of the schema. |
| classpath | The colon separated list of jar names. |
add_type_mapping
The add_type_mapping command installs a mapping between a SQL type and a Java
class. Once the mapping is in place, parameters and return values will be
mapped accordingly. Please read [[Mapping an SQL type to a Java class]] for
detailed information.
Usage
SELECT sqlj.add_type_mapping(<sql type>, <java class>);
| Parameter | Description |
|---|---|
| sql type | The name of the SQL type. The name can be qualified with a schema (namespace). If the schema is omitted, it will be resolved according to the current setting of the search_path. |
| java class | The name of the class. The class must be found in the classpath in effect for the current schema |
drop_type_mapping
The drop_type_mapping command removes a mapping between a SQL type and a Java
class.
Usage
SELECT sqlj.drop_type_mapping(<sql type>);
| Parameter | Description |
|---|---|
| sql type | The name of the SQL type. The name can be qualified with a schema (namespace). If the schema is omitted, it will be resolved according to the current setting of the search_path. |
Note on jar URLs
The install_jar and replace_jar commands accept a URL (that must be
reachable from the server) to a jar file. It is even possible, using the
rules for jar URLs, to construct one that refers to a jar file within
another jar file. For example:
jar:file:outer.jar!/inner.jar
However, Java’s caching of the “outer” jar may frustrate attempts to replace or reload a newer version within the same session.