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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Query complexity</span></span>
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<div id="mw-content-text" class="mw-body-content mw-content-ltr" lang="en" dir="ltr"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><p><b>Query complexity</b> in <a href="Computational_complexity" title="Computational complexity">computational complexity</a> describes the number of queries needed to solve a computational problem for an input that can be accessed only through queries. See in particular:
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<ul><li><a href="Aanderaa%E2%80%93Karp%E2%80%93Rosenberg_conjecture" title="Aanderaa–Karp–Rosenberg conjecture">Aanderaa–Karp–Rosenberg conjecture</a>, on the query complexity of graph problems accessed by querying the existence of edges</li>
<li><a href="Property_testing" title="Property testing">Property testing</a>, the study of query complexity for distinguishing objects having a property from objects far from having it</li>
<li><a href="Probabilistically_checkable_proof" title="Probabilistically checkable proof">Probabilistically checkable proof</a>, a proof that can be verified by making a small number of queries to the bits of the proof</li>
<li><a href="Quantum_complexity_theory#Quantum_query_complexity" title="Quantum complexity theory">Quantum complexity theory#Quantum query complexity</a>, the number of queries needed to solve a problem using a quantum algorithm</li>
<li>Query complexity in the <a href="Decision_tree_model" title="Decision tree model">decision tree model</a>, the number of queries needed to solve a computational problem by an algorithm that is restricted to take the form of a decision tree</li>
<li><a href="Decision_tree_model#Quantum_decision_tree" title="Decision tree model">Decision tree model#Quantum decision tree</a>, decision tree complexity for a quantum decision tree</li>
<li><a href="Equitable_cake-cutting#Query_complexity" title="Equitable cake-cutting">Equitable cake-cutting#Query complexity</a>, the number of times one must query participant preferences in a fair sharing procedure</li></ul>
<div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2></div>
<ul><li><a href="Query_evaluation#Formal_definition" title="Query evaluation">Query complexity</a> in database theory, the complexity of evaluating a query on a database when measured as a function of the query size</li>
<li><a href="Query_(complexity)" title="Query (complexity)">Query (complexity)</a>, a mapping between logical structures in descriptive complexity</li></ul>
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