From ab9484b343abd995cba915bb0ba4be8907dfa6ec Mon Sep 17 00:00:00 2001 From: Gregor Kleen Date: Fri, 13 Nov 2015 23:45:26 +0000 Subject: Shorter lecture names --- ws2015/dbs/blaetter/04/abgabe.md | 15 +++++++++++++++ 1 file changed, 15 insertions(+) create mode 100644 ws2015/dbs/blaetter/04/abgabe.md (limited to 'ws2015/dbs/blaetter/04') diff --git a/ws2015/dbs/blaetter/04/abgabe.md b/ws2015/dbs/blaetter/04/abgabe.md new file mode 100644 index 0000000..708a249 --- /dev/null +++ b/ws2015/dbs/blaetter/04/abgabe.md @@ -0,0 +1,15 @@ +--- +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) $\pi_{\texttt{T.tname}}(\sigma_{\texttt{P.ort} = \text{Berlin}}(\texttt{P} \bowtie \texttt{LTP} \bowtie \texttt{T}))$ -- cgit v1.2.3