Loading data into tables with geospatial columns using SQL Loader.

12 Oct 2023

In this tutorial, we will explore how to load data into tables with geospatial columns using SQL Loader. SQL Loader is a utility provided by Oracle to efficiently load data from external files into Oracle database tables. If you have geospatial data in your files and you want to load it into your tables, SQL Loader provides an easy and efficient method to do so.

Prerequisites

Before we start, make sure that you have the following prerequisites in place:

Oracle Database installed and running.
Access to the SQL Loader utility.

Step 1: Create a table with geospatial columns

First, we need to create a table with geospatial columns in the Oracle database. For example, let’s create a table called locations with the following columns:

id (number)
name (varchar2)
longitude (sdo_geometry)
latitude (sdo_geometry)

To create this table, you can use the following SQL statement:

CREATE TABLE locations (
    id NUMBER,
    name VARCHAR2(100),
    longitude SDO_GEOMETRY,
    latitude SDO_GEOMETRY
);

Step 2: Create a control file

Next, we need to create a control file that describes how the data in our external file should be loaded into the table. The control file specifies the format of the data file, the table structure, and any transformations that need to be applied.

Here is an example of a control file called locations.ctl for loading data into the locations table:

LOAD DATA
INFILE 'locations.txt'
INTO TABLE locations
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
(
    id,
    name,
    longitude "sdo_geometry(2001, 4326)",
    latitude "sdo_geometry(2001, 4326)"
)

Step 3: Prepare the data file

Now, you need to prepare the data file locations.txt that contains the data you want to load into the table. Make sure that the data in the file is structured according to the control file and the table structure.

For example, the locations.txt file may have the following content:

1,"Location 1",SDO_GEOMETRY(2001, 4326, SDO_POINT_TYPE(10, 20, NULL), NULL)
2,"Location 2",SDO_GEOMETRY(2001, 4326, SDO_POINT_TYPE(30, 40, NULL), NULL)

Step 4: Run SQL Loader

Once you have the control file and the data file prepared, you can run the SQL Loader utility to load the data into the table.

Open a command prompt or terminal and navigate to the directory where the control file and the data file are located.

Use the following command to run SQL Loader and load the data into the table:

sqlldr username/password control=locations.ctl

Replace username and password with your Oracle database username and password.

Conclusion

By following the steps outlined in this tutorial, you should now be able to load data into tables with geospatial columns using SQL Loader. SQL Loader provides a simple and efficient way to load geospatial data from external files into an Oracle database. This can be particularly useful when dealing with large datasets or performing bulk data loading tasks.

Remember to adapt the table schema, control file, and data file structure to match your specific use case. Happy loading!

#SQLLoader #GeospatialData