More wordsmithing

This commit is contained in:
Andrew M. Kuchling 2006-09-12 21:21:51 +00:00
parent 32cec80b02
commit ab856873f1

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@ -146,8 +146,8 @@ committed. The \var{timeout} parameter specifies how long the connection should
wait for the lock to go away until raising an exception. The default for the wait for the lock to go away until raising an exception. The default for the
timeout parameter is 5.0 (five seconds). timeout parameter is 5.0 (five seconds).
For the \var{isolation_level} parameter, please see \member{isolation_level} For the \var{isolation_level} parameter, please see the \member{isolation_level}
\ref{sqlite3-Connection-IsolationLevel} property of \class{Connection} objects. property of \class{Connection} objects in section~\ref{sqlite3-Connection-IsolationLevel}.
SQLite natively supports only the types TEXT, INTEGER, FLOAT, BLOB and NULL. If SQLite natively supports only the types TEXT, INTEGER, FLOAT, BLOB and NULL. If
you want to use other types, like you have to add support for them yourself. you want to use other types, like you have to add support for them yourself.
@ -212,13 +212,14 @@ A \class{Connection} instance has the following attributes and methods:
\label{sqlite3-Connection-IsolationLevel} \label{sqlite3-Connection-IsolationLevel}
\begin{memberdesc}{isolation_level} \begin{memberdesc}{isolation_level}
Get or set the current isolation level. None for autocommit mode or one of Get or set the current isolation level. None for autocommit mode or one of
"DEFERRED", "IMMEDIATE" or "EXLUSIVE". See Controlling Transactions "DEFERRED", "IMMEDIATE" or "EXLUSIVE". See ``Controlling Transactions'',
\ref{sqlite3-Controlling-Transactions} for a more detailed explanation. section~\ref{sqlite3-Controlling-Transactions}, for a more detailed explanation.
\end{memberdesc} \end{memberdesc}
\begin{methoddesc}{cursor}{\optional{cursorClass}} \begin{methoddesc}{cursor}{\optional{cursorClass}}
The cursor method accepts a single optional parameter \var{cursorClass}. The cursor method accepts a single optional parameter \var{cursorClass}.
This is a custom cursor class which must extend \class{sqlite3.Cursor}. If supplied, this must be a custom cursor class that extends
\class{sqlite3.Cursor}.
\end{methoddesc} \end{methoddesc}
\begin{methoddesc}{execute}{sql, \optional{parameters}} \begin{methoddesc}{execute}{sql, \optional{parameters}}
@ -244,7 +245,7 @@ parameters given.
Creates a user-defined function that you can later use from within SQL Creates a user-defined function that you can later use from within SQL
statements under the function name \var{name}. \var{num_params} is the number statements under the function name \var{name}. \var{num_params} is the number
of parameters the function accepts, and \var{func} is a Python callable that is of parameters the function accepts, and \var{func} is a Python callable that is
called as SQL function. called as the SQL function.
The function can return any of the types supported by SQLite: unicode, str, The function can return any of the types supported by SQLite: unicode, str,
int, long, float, buffer and None. int, long, float, buffer and None.
@ -274,7 +275,7 @@ Example:
Creates a collation with the specified \var{name} and \var{callable}. The Creates a collation with the specified \var{name} and \var{callable}. The
callable will be passed two string arguments. It should return -1 if the first callable will be passed two string arguments. It should return -1 if the first
is ordered lower than the second, 0 if they are ordered equal and 1 and if the is ordered lower than the second, 0 if they are ordered equal and 1 if the
first is ordered higher than the second. Note that this controls sorting first is ordered higher than the second. Note that this controls sorting
(ORDER BY in SQL) so your comparisons don't affect other SQL operations. (ORDER BY in SQL) so your comparisons don't affect other SQL operations.
@ -323,20 +324,21 @@ module.
\begin{memberdesc}{row_factory} \begin{memberdesc}{row_factory}
You can change this attribute to a callable that accepts the cursor and You can change this attribute to a callable that accepts the cursor and
the original row as tuple and will return the real result row. This the original row as a tuple and will return the real result row. This
way, you can implement more advanced ways of returning results, like way, you can implement more advanced ways of returning results, such
ones that can also access columns by name. as returning an object that can also access columns by name.
Example: Example:
\verbatiminput{sqlite3/row_factory.py} \verbatiminput{sqlite3/row_factory.py}
If the standard tuple types don't suffice for you, and you want name-based If returning a tuple doesn't suffice and you want name-based
access to columns, you should consider setting \member{row_factory} to the access to columns, you should consider setting \member{row_factory} to the
highly-optimized sqlite3.Row type. It provides both highly-optimized \class{sqlite3.Row} type. \class{Row} provides both
index-based and case-insensitive name-based access to columns with almost index-based and case-insensitive name-based access to columns with almost
no memory overhead. Much better than your own custom dictionary-based no memory overhead. It will probably be better than your own custom
approach or even a db_row based solution. dictionary-based approach or even a db_row based solution.
% XXX what's a db_row-based solution?
\end{memberdesc} \end{memberdesc}
\begin{memberdesc}{text_factory} \begin{memberdesc}{text_factory}
@ -350,7 +352,7 @@ module.
attribute to \constant{sqlite3.OptimizedUnicode}. attribute to \constant{sqlite3.OptimizedUnicode}.
You can also set it to any other callable that accepts a single bytestring You can also set it to any other callable that accepts a single bytestring
parameter and returns the result object. parameter and returns the resulting object.
See the following example code for illustration: See the following example code for illustration:
@ -358,7 +360,7 @@ module.
\end{memberdesc} \end{memberdesc}
\begin{memberdesc}{total_changes} \begin{memberdesc}{total_changes}
Returns the total number of database rows that have be modified, inserted, Returns the total number of database rows that have been modified, inserted,
or deleted since the database connection was opened. or deleted since the database connection was opened.
\end{memberdesc} \end{memberdesc}
@ -385,9 +387,9 @@ This example shows how to use the named style:
\verbatiminput{sqlite3/execute_2.py} \verbatiminput{sqlite3/execute_2.py}
\method{execute} will only execute a single SQL statement. If you try to \method{execute()} will only execute a single SQL statement. If you try to
execute more than one statement with it, it will raise a Warning. Use execute more than one statement with it, it will raise a Warning. Use
\method{executescript} if want to execute multiple SQL statements with one \method{executescript()} if you want to execute multiple SQL statements with one
call. call.
\end{methoddesc} \end{methoddesc}
@ -395,7 +397,7 @@ This example shows how to use the named style:
\begin{methoddesc}{executemany}{sql, seq_of_parameters} \begin{methoddesc}{executemany}{sql, seq_of_parameters}
Executes a SQL command against all parameter sequences or mappings found in the Executes a SQL command against all parameter sequences or mappings found in the
sequence \var{sql}. The \module{sqlite3} module also allows sequence \var{sql}. The \module{sqlite3} module also allows
to use an iterator yielding parameters instead of a sequence. using an iterator yielding parameters instead of a sequence.
\verbatiminput{sqlite3/executemany_1.py} \verbatiminput{sqlite3/executemany_1.py}
@ -407,7 +409,7 @@ Here's a shorter example using a generator:
\begin{methoddesc}{executescript}{sql_script} \begin{methoddesc}{executescript}{sql_script}
This is a nonstandard convenience method for executing multiple SQL statements This is a nonstandard convenience method for executing multiple SQL statements
at once. It issues a COMMIT statement before, then executes the SQL script it at once. It issues a COMMIT statement first, then executes the SQL script it
gets as a parameter. gets as a parameter.
\var{sql_script} can be a bytestring or a Unicode string. \var{sql_script} can be a bytestring or a Unicode string.
@ -558,8 +560,8 @@ database is actually a point. There are two ways of doing this:
\item Explicitly via the column name \item Explicitly via the column name
\end{itemize} \end{itemize}
Both ways are described in section~\ref{sqlite3-Module-Contents}, in Both ways are described in ``Module Constants'', section~\ref{sqlite3-Module-Contents}, in
the text explaining the constants \constant{PARSE_DECLTYPES} and the entries for the constants \constant{PARSE_DECLTYPES} and
\constant{PARSE_COLNAMES}. \constant{PARSE_COLNAMES}.
@ -619,17 +621,17 @@ the connection yourself.
Using the nonstandard \method{execute}, \method{executemany} and Using the nonstandard \method{execute}, \method{executemany} and
\method{executescript} methods of the \class{Connection} object, your code can \method{executescript} methods of the \class{Connection} object, your code can
be written more concisely, because you don't have to create the - often be written more concisely because you don't have to create the (often
superfluous \class{Cursor} objects explicitly. Instead, the \class{Cursor} superfluous) \class{Cursor} objects explicitly. Instead, the \class{Cursor}
objects are created implicitly and these shortcut methods return the cursor objects are created implicitly and these shortcut methods return the cursor
objects. This way, you can for example execute a SELECT statement and iterate objects. This way, you can execute a SELECT statement and iterate
over it directly using only a single call on the \class{Connection} object. over it directly using only a single call on the \class{Connection} object.
\verbatiminput{sqlite3/shortcut_methods.py} \verbatiminput{sqlite3/shortcut_methods.py}
\subsubsection{Accessing columns by name instead of by index} \subsubsection{Accessing columns by name instead of by index}
One cool feature of the \module{sqlite3} module is the builtin \class{sqlite3.Row} class One useful feature of the \module{sqlite3} module is the builtin \class{sqlite3.Row} class
designed to be used as a row factory. designed to be used as a row factory.
Rows wrapped with this class can be accessed both by index (like tuples) and Rows wrapped with this class can be accessed both by index (like tuples) and