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29 lines
1.1 KiB
Python
29 lines
1.1 KiB
Python
# Sebastian Raschka, 2014
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# Adding a new column to an existing SQLite database
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import sqlite3
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sqlite_file = 'my_first_db.sqlite' # name of the sqlite database file
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table_name = 'my_table_2' # name of the table to be created
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id_column = 'my_1st_column' # name of the PRIMARY KEY column
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new_column1 = 'my_2nd_column' # name of the new column
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new_column2 = 'my_3rd_column' # name of the new column
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column_type = 'TEXT' # E.g., INTEGER, TEXT, NULL, REAL, BLOB
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default_val = 'Hello World' # a default value for the new column rows
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# Connecting to the database file
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conn = sqlite3.connect(sqlite_file)
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c = conn.cursor()
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# A) Adding a new column without a row value
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c.execute("ALTER TABLE {tn} ADD COLUMN '{cn}' {ct}"\
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.format(tn=table_name, cn=new_column1, ct=column_type))
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# B) Adding a new column with a default row value
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c.execute("ALTER TABLE {tn} ADD COLUMN '{cn}' {ct} DEFAULT '{df}'"\
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.format(tn=table_name, cn=new_column2, ct=column_type, df=default_val))
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# Committing changes and closing the connection to the database file
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conn.commit()
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conn.close()
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