70 lines
1.1 KiB
Python
70 lines
1.1 KiB
Python
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"""
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A collection of update operations for TinyDB.
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They are used for updates like this:
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>>> db.update(delete('foo'), where('foo') == 2)
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This would delete the ``foo`` field from all documents where ``foo`` equals 2.
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"""
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def delete(field):
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"""
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Delete a given field from the document.
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"""
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def transform(doc):
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del doc[field]
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return transform
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def add(field, n):
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"""
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Add ``n`` to a given field in the document.
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"""
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def transform(doc):
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doc[field] += n
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return transform
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def subtract(field, n):
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"""
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Subtract ``n`` to a given field in the document.
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"""
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def transform(doc):
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doc[field] -= n
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return transform
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def set(field, val):
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"""
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Set a given field to ``val``.
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"""
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def transform(doc):
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doc[field] = val
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return transform
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def increment(field):
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"""
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Increment a given field in the document by 1.
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"""
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def transform(doc):
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doc[field] += 1
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return transform
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def decrement(field):
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"""
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Decrement a given field in the document by 1.
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"""
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def transform(doc):
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doc[field] -= 1
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return transform
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