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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) $\pi_{\texttt{T.tname}}(\sigma_{\texttt{P.ort} = \text{Berlin}}(\texttt{P} \bowtie \texttt{LTP} \bowtie \texttt{T}))$