[DMDB] Fix issues, improve query processing with notes on time complexities

semester4/dmdb/parts/04_query-processing/04_join/08_partitioned-hash-join.tex

@@ -20,4 +20,4 @@ The benefit of this approach is that in the third step, we are only operating on
 What we ideally do in the above algorithm is to do \textit{recursive partitioning}, i.e. as already \textit{somewhat} described, we partition each partition again,
 if it has more than one page. This further reduces access times.
 
-The cost for this is $3 \cdot (P_S + P_R)$, thus both OSMJ and PHJ are very similar in performance.
+The cost for this is \cost{$3 \cdot (P_S + P_R)$}, thus both OSMJ and PHJ are very similar in performance.