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#Sqlite list tables python how to
#Sqlite list tables python code

# Create database connection to a main database which is stored in a fileĬonnectionObject = nnect("info.dbs") The Python example below queries the sqlite_master table and prints the list of tables and indices present in the SQLite main database loaded through the file info.dbs.A SQL statement like a SELECT statement can be executed on the SQLite server by calling the execute() method of the cursor object and passing the SQL statement as parameter.Through the connection object a sqlite3.Cursor object can be obtained.A database connection to an SQLite database can be created by calling the connect() method of the sqlite3 module.The sqlite3 is the python database client for SQLite database.Getting the list of tables and indexes present in a SQLite database using Python: The sql column of the sqlite_master table contains the SQL statement with which a table or index has been created.The type column will hold the value "table" for a database table and the value "index" for a database index.

The type column of the sqlite_master table denotes what type of database object the record is about.

The sqlite_master table of a database contains the list of tables, indices and other details specific to that database.

Every SQLite database has a special table named sqlite_master, which is a system created table.

#Sqlite list tables python how to

In this tutorial, you have learned how to use the SQLite IN operator to match a value with a list of values or a subquery.

#Sqlite list tables python code

Genreid NOT IN ( 1, 2, 3) Code language: SQL (Structured Query Language) ( sql ) The following statement returns a list of tracks whose genre id is not in a list of (1,2,3).

Then, the outer query return all tracks whose album id matches with the album id list returned by the subquery.

First, the subquery returns a list of album ids that belong to the artist id 12.

) Code language: SQL (Structured Query Language) ( sql ) To get the tracks that belong to the artist id 12, you can combine the IN operator with a subquery as follows: SELECT WHERE artistid = 12 Code language: SQL (Structured Query Language) ( sql ) The following query returns a list of album id of the artist id 12: SELECT albumid SQLite IN operator with a subquery example To negate the list of values, you use the NOT IN operator. The IN operator returns true or false depending on whether the expression matches any value in a list of values or not. The returned type of expression and values in the list must be the same. Second, create a Cursor object by calling the cursor () method of the Connection object. A list of values is a fixed value list or a result set of a single column returned by a subquery. If you have a query that uses many OR operators, you can consider using the IN operator instead to make the query more readable. To create a new table in an SQLite database from a Python program, you use the following steps: First, create a Connection object using the connect () function of the sqlite3 module. MediaTypeId = 1 OR MediaTypeId = 2 ORDER BY Name ASC Code language: SQL (Structured Query Language) ( sql )Īs you can see from the queries, using the IN operator is much shorter.

This query uses the OR operator instead of the IN operator to return the same result set as the above query: SELECT ORDER BY Name ASC Code language: SQL (Structured Query Language) ( sql ) The following statement uses the IN operator to query the tracks whose media type id is 1 or 2. We will use the Tracks table from the sample database for the demonstration. The expression can be any valid expression or a column of a table.Ī list of values is a fixed value list or a result set of a single column returned by a subquery. The syntax of the IN operator is as follows: expression IN (value_list|subquery) Code language: SQL (Structured Query Language) ( sql ) The SQLite IN operator determines whether a value matches any value in a list or a subquery. Summary: in this tutorial, you will learn how to use the SQLite IN operator to determine whether a value matches any value in a list of values or a result of a subquery.