+
+proc explain {query} {
+ global ok pref
+
+ set ok 0
+ z.1 databaseNames IR-Explain-1
+ z.1 preferredRecordSyntax explain
+ z callback {find-response z.1}
+ z.1 search "@attrset exp1 @attr 1=1 @attr 2=3 @attr 3=3 @attr 4=3 $query"
+ vwait ok
+ return {}
+}