Schema Spy uses the dot executable from graphviz to generate the graphical representation of the schema and its relationship. Graphviz is the graphics visualization software that takes descriptions of graphs in a simple text language, and make diagrams in several useful formats such as images and SVG for web pages, Postscript for inclusion in PDF or other documents; or display in an interactive graph browser.
Following is the steps to execute the SchemaSpy tool (for a sample MYSQL database.)
1. Download and install Graphviz from http://www.graphviz.org/Download..php
2. Download the Schema spay jar file, Schemaspy_x_y_z.jar from http://sourceforge.net/projects/schemaspy/files/
3. Download the corresponding JDBC Connector and have it on the same source folder where the schemaspy_x_y_z.jar resides. For example for a mysql database, I would simply download mysql-connector-java-5.1.5.jar or any other latest version of mysql connector.
4. Now from the source location of your Schemaspy_x_y_z.jar file, execute schemaspy to generate the graphical representation of the schema of your database, as shown on the following syntax
java -jar schemaSpy_x.y.z.jar -t database_type -dp mysql jdbcdatabase_connector -hq -o output_Directory -db databaseName -u username -p password
for example : java -jar schemaSpy_4.1.1.jar -t mysql -dp mysql-connector-java-5.1.5.jar -hq -o out -db bisudatabae -u bishow -p north