Assessment of Urban Water Supply System Based on Query Optimization Strategy

<table class="table-group" id="tab2"><tr><td><table class="table"><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr class="thead"><td class="align_left">Relation</td><td class="align_center">Card</td><td class="align_center">Size</td></tr><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr><td class="align_left">G</td><td class="align_center">30</td><td class="align_center">1500</td></tr><tr><td class="align_left">E</td><td class="align_center">100</td><td class="align_center">3000</td></tr><tr><td class="align_left">J</td><td class="align_center">50</td><td class="align_center">2000</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Query graph for semijoin program.</div>

Complexity

tab2

Table 2

Table 2: Assessment of Urban Water Supply System Based on Query Optimization Strategy 