@@ -184,7 +184,7 @@ The first section of the \texttt{'planets.json'} file is given in Listing~\ref{l
The contents of \texttt{select\_planet.py} are given in Listing~\ref{listing:select_planet.py}. This Python program prints the names of the collections and then checks if the \texttt{'orbit\_data'} collection is present. If the \texttt{'OrbitData'} collection is present, it prints the names of each of the planets and the complete document for Pluto.
The \texttt{find} function at Line 26 includes two arguments, which are each given within \texttt{\{\}} parentheses. The first pair of \texttt{\{\}} parentheses is empty. This is the condition, which is optional. Since the condition is empty, all documents are considered. The second argument is \texttt{\{'name':1, '\_id':0 \}}. The second argument is a list of document fields that should be considered. The format is the field name, a colon and the position number. Setting the position number to zero for the \texttt{\_id} field causes it not to be printed.
The \texttt{find} function at Line 26 includes two arguments, which are each given within \texttt{\{\}} parentheses. The first pair of \texttt{\{\}} parentheses is empty. This is the query condition, which is optional. Since the condition is empty, all documents are considered. The second argument is \texttt{\{'name':1, '\_id':0 \}}. The second argument is a list of document fields that should be enabled or disabled. The format is the field name, a colon and an integer number, where 0 disables the field and 1 enables the field. In general, the \texttt{find} command allows up to three input arguments, as discussed in the \href{https://www.mongodb.com/docs/manual/reference/method/db.collection.find/#mongodb-method-db.collection.find}{MongoDB documenation}.
The \texttt{find\_one} function at Line 32 includes a condition that the field \texttt{'name'} must be equal to \texttt{'Pluto'}. Since the list of fields to be considered is omitted, all fields are returned.
