Examples with FromTerm org.apache.asterix.lang.sqlpp.clause.FromTerm used on opensource projects

Example 11 with FromTerm

use of org.apache.asterix.lang.sqlpp.clause.FromTerm in project asterixdb by apache.

the class FreeVariableVisitor method visit.

@Override
public Void visit(FromClause fromClause, Collection<VariableExpr> freeVars) throws CompilationException {
    Collection<VariableExpr> bindingVars = new HashSet<>();
    for (FromTerm fromTerm : fromClause.getFromTerms()) {
        Collection<VariableExpr> fromTermFreeVars = new HashSet<>();
        fromTerm.accept(this, fromTermFreeVars);
        // Since a right from term can refer to variables defined in a left from term,
        // we remove binding variables from the free variables.
        fromTermFreeVars.removeAll(bindingVars);
        // Adds binding variables.
        bindingVars.addAll(SqlppVariableUtil.getBindingVariables(fromTerm));
        // Adds into freeVars.
        freeVars.addAll(fromTermFreeVars);
    }
    return null;
}