public void setPrepareSql(String sql) {
		this.prepareSql = sql;
	}
Utility class helping to execute jdbc operations within a load session.
Provides a way to prepare, run and clean a main load command. Additionally
it can use a list of before and after commands which are execute before and after
of a main command. Clean command is executed last even if some of the other
commands fail.

@author Janne Valkealahti
extensions/spring-xd-extension-gpfdist/src/main/java/org/springframework/xd/greenplum/support/JdbcCommands.java