The IN operator returns true or false depending on whether the expression matches any value in a list of values or not. We will use the Tracks table from the sample database for the demonstration. The following statement uses the IN operator to query the tracks whose media type id is 1 or 2.
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Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Does ES6 make JavaScript frameworks obsolete? Sometimes, you may not remember exactly the data that you want to search. In this case, you perform an inexact search using the LIKE operator. The IN operator allows you to check whether a value is in a list of a comma-separated list of values. For example, to find tracks that have media type id is 2 or 3, you use the IN operator as shown in the following statement:.
Up Next. This includes SELECT statements because we cannot determine the number of rows a query produced until all rows were fetched.
This read-only attribute provides the rowid of the last modified row. The default value is 1 which means a single row would be fetched per call. This read-only attribute provides the column names of the last query.
A Cursor object created by calling con. It tries to mimic a tuple in most of its features. It supports mapping access by column name and index, iteration, representation, equality testing and len. If two Row objects have exactly the same columns and their members are equal, they compare equal. This method returns a list of column names. Immediately after a query, it is the first member of each tuple in Cursor.
Now we plug Row in:. A subclass of Exception. The base class of the other exceptions in this module. It is a subclass of Exception. Exception raised when the relational integrity of the database is affected, e. It is a subclass of DatabaseError. Exception raised for programming errors, e. Exception raised in case a method or database API was used which is not supported by the database, e. The type system of the sqlite3 module is extensible in two ways: you can store additional Python types in a SQLite database via object adaptation, and you can let the sqlite3 module convert SQLite types to different Python types via converters.
As described before, SQLite supports only a limited set of types natively. There are two ways to enable the sqlite3 module to adapt a custom Python type to one of the supported ones. This is a good approach if you write the class yourself. Now you want to store the point in a single SQLite column. The parameter protocol will be PrepareProtocol. Writing an adapter lets you send custom Python types to SQLite.
We stored the x and y coordinates separated via semicolons as strings in SQLite. Converter functions always get called with a bytes object, no matter under which data type you sent the value to SQLite. Now you need to make the sqlite3 module know that what you select from the database is actually a point.
There are two ways of doing this:. There are default adapters for the date and datetime types in the datetime module. If a timestamp stored in SQLite has a fractional part longer than 6 numbers, its value will be truncated to microsecond precision by the timestamp converter. The underlying sqlite3 library operates in autocommit mode by default, but the Python sqlite3 module by default does not.
This will leave the underlying sqlite3 library operating in autocommit mode. This is no longer the case. Instead, the Cursor objects are created implicitly and these shortcut methods return the cursor objects. One useful feature of the sqlite3 module is the built-in sqlite3.
Row class designed to be used as a row factory. Rows wrapped with this class can be accessed both by index like tuples and case-insensitively by name:. Connection objects can be used as context managers that automatically commit or rollback transactions.
In the event of an exception, the transaction is rolled back; otherwise, the transaction is committed:. The sqlite3 module is not built with loadable extension support by default, because some platforms notably macOS have SQLite libraries which are compiled without this feature. To get loadable extension support, you must pass the --enable-loadable-sqlite-extensions option to configure.
Navigation index modules next previous Python ». Just be sure any changes have been committed or they will be lost. Never do this -- insecure! Error as e : print "An error occurred:" , e. New in version 3. Note Exceptions raised in the trace callback are not propagated.
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