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51 lines
1.2 KiB
Python
51 lines
1.2 KiB
Python
# Sebastian Raschka, 2014
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# Updating rows in an existing SQLite database
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import sqlite3
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sqlite_file = ''
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table_name = ''
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column_name_1 = ''
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column_name_2 = ''
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column_name_3 = ''
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value_1 = 'hello world'
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value_2 = 12345
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conn = sqlite3.connect(sqlite_file)
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c = conn.cursor()
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# A.1) Updating all rows for a single column
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c.execute('UPDATE {dn} SET {cn1}={v1}'.\
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format(dn=table_name, cn1=column_name_1, v1=value1)
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# A.2) Updating all rows for 2 columns (same for multiple columns)
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c.execute('UPDATE {dn} SET {cn1}={v1}, {cn2}={v2}'.\
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format(dn=table_name, cn1=column_name_1, cn2=column_name_2,
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v1=value1, v2=value2)
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# B.1) Updating specific rows that meet a certain criterion
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# here: update column_1 with value_1 if row has value_2 in column_2
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c.execute('UPDATE {dn} SET {cn1}={v1} WHERE {cn2}={v2}'.\
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format(dn=table_name, cn1=column_name_1, v1=value1)
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# B.2) Updating specific rows that meet multiple criteria
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# here: update column_1 with value_1
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# if row has value_2 in column_2
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# and if row has value = 1 in column_3
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c.execute('UPDATE {dn} SET {cn1}={v1} WHERE {cn2}={v2} AND {cn3}=1'.\
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format(dn=table_name, cn1=column_name_1, v1=value1, cn3=column_name_3)
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conn.commit()
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conn.close()
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