User defined function, class creation for external data source access
An example technique for defining a user function can include receiving a user defined function that gathers data from a data source external to a database and returns the data to the database. The example technique for defining the user function can also include creating an instance of a programming class that extends from an application programming interface (API). The instance of the programming class including the user defined function. The example technique for defining the user function can also include executing the user defined function provided by the instance of the programming class.
1. A system for user defined functions, comprising:
a processor; and
a computer-readable medium comprising machine-readable instructions executable by the processor to:
receive a user defined function, wherein the user defined function is to gather data from a data source external to a database utilizing a function-scan that searches content from a non-table resource of the data source according to a particular function and to return the data to the database;
create an instance of a programming class that extends from an application programming interface (API), wherein the instance of the programming class includes the user defined function and a number of user-defined parameters for gathering the data from the data source external to the database, and enables a template that allows a user to communicate with the database and the data source external to the database; and
execute the user defined function provided by the instance of the programming class to gather the data from the data source external to the database.
2. The system of claim 1 , wherein the machine-readable instructions cause the processor to:
provide the user defined function.
3. The system of claim 2 , wherein the machine-readable instructions cause the processor to:
provide a query that includes the user defined function.
4. The system of claim 3 , wherein the machine-readable instructions cause the processor to:
execute the query to retrieve the data from the data source via the user defined function.
5. The system of claim 4 , wherein the data is stored in the database.
6. The system of claim 5 , wherein the query is composed of syntax that is associated with the query engine and syntax that is associated with the external data source.
7. A non-transitory machine-readable medium storing instructions for defining user function, the instructions executable by a machine to cause the machine to:
provide a user defined transformation function (UDTF) that gathers data from a data source platform external to a query engine, wherein the UDTF provides a function-scan that searches content from a non-table resource of the data source platform according to a particular function;
provide access to the UDTF via a plurality of programming classes, wherein the plurality of programming classes each include a number of user-defined parameters for gathering the data from the data source platform to the query engine, and enables a template that allows a user to communicate with the query engine and the data source platform;
execute via the query engine the UDTF received from the plurality of programming classes to gather the data from the data source platform;
receive data from the data source platform; and
store the data in a database.
8. The medium of claim 7 , wherein the data source platform stores non-relational data and the query engine is associated with the database that stores relational data.
9. The medium of claim 8 , wherein the data can be retrieved from the data source platform by executing the UDTF.
10. A method for defining user function comprising:
abstracting an interface to a data source platform via a plurality of programming classes;
implementing the plurality of programming classes using a plurality of parameters of the data source platform and a user defined transformation function (UDTF), wherein the UDTF provides function-scan that searches content from a non-table resource of the data source platform according to a particular function, wherein the plurality of programming classes each include a number of user-defined parameters for gathering the data from the data source platform, and enables a template allowing a user to communicate with the data source platform;
registering the UDTF with the query engine using the plurality of programming classes; and
executing the UDTF using the query engine to gather the data from the data source platform.
11. The method of claim 10 , wherein executing the UDTF includes executing the plurality of programming classes.
12. The method of claim 10 , wherein the plurality of programming classes include at least a function class and a function wrapper class.
13. The method of claim 12 , wherein the function class includes instructions to connect a database to the data source platform and retrieving data from the data source platform.
14. The method of claim 13 , wherein the function wrapper class includes an application programming interface (API) for registering the UDTF and parameters associated with the UDTF with the database.