**3.7.1 Example**

Considering, another scenario having predicates conditions with disjunctive operator in Figure 10. All the three branches yields to clash in checking *Q3* ⊑ *Q4;* therefore, *Q4* contain *Q3*. In first branch (Line 8 in Figure 10) after applying the *Or rule, Emp* and ⇁*Emp* yields to clash. In second branch (Line 9 in Figure 10) *ename* and ⇁*ename* yields to clash, and in third *branch (Line 10* Figure 10), *≥30k(sal)* and *≤19k(sal)* yields to clash. All tree branches (Line 8, 9, 10 of Figure 10) yield to clash in opening the tableaux algorithm; therefore, *Q3* ⊑ *Q4.* 


Fig. 10. Query Containment using Tableux.
