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+---
+header-includes:
+        - \usepackage{amsmath}
+        - \usepackage{amssymb}
+---
+
+# Natural Join
+
+Zu $\land$.
+
+# Anfragen in relationaler Algebra
+
+a) $\pi_{\texttt{P.pname}}(\sigma_{\texttt{P.ort} = \text{Berlin}}(\texttt{P}))$
+b) $\pi_{\texttt{T.tnr}} \left ( \sigma_{\texttt{L.lname} = \text{Meier}} \left ( \texttt{L} \bowtie \texttt{LTP} \texttt{T} \right ) \right )$
+c) $\pi_{\texttt{T.tname}}(\sigma_{\texttt{P.ort} = \text{Berlin}}(\texttt{P} \bowtie \texttt{LTP} \bowtie \texttt{T}))$