There are a new commands in 4D v11 SQL which allow you to create, modify, rebuild and delete indexes dynamically. The syntax of the commands follows:

SET INDEX(Field; index{;mode{;*}})

CREATE INDEX(Table;fieldsArray;indexType;indexName{;*})

DELETE INDEX(fieldPtr|indexName{;*})

The SET INDEX command creates an index of the type specified by the "index" parameter. This parameter is overloaded and can take either a boolean or integer type value.

For more information see the documentation topic Structure Access.