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Albert Tugushev
a836e3df5d
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### Description
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Remove print statements
### Checklist
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This pull request is:
- [X] A documentation / typographical error fix
- Good to go, no issue or tests are needed
- [ ] A short code fix
- please include the issue number, and create an issue if none exists, which
must include a complete example of the issue. one line code fixes without an
issue and demonstration will not be accepted.
- Please include: `Fixes: #<issue number>` in the commit message
- please include tests. one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
- please include the issue number, and create an issue if none exists, which must
include a complete example of how the feature would look.
- Please include: `Fixes: #<issue number>` in the commit message
- please include tests.
**Have a nice day!**
Closes: #5166
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5166
Pull-request-sha: 04a7394f71
Change-Id: Ib90a59fac929661a18748c6e44966fb87e3978c6
35 lines
1.0 KiB
Python
35 lines
1.0 KiB
Python
"""
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Illustrates "vertical table" mappings.
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A "vertical table" refers to a technique where individual attributes
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of an object are stored as distinct rows in a table. The "vertical
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table" technique is used to persist objects which can have a varied
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set of attributes, at the expense of simple query control and brevity.
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It is commonly found in content/document management systems in order
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to represent user-created structures flexibly.
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Two variants on the approach are given. In the second, each row
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references a "datatype" which contains information about the type of
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information stored in the attribute, such as integer, string, or date.
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Example::
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shrew = Animal(u'shrew')
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shrew[u'cuteness'] = 5
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shrew[u'weasel-like'] = False
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shrew[u'poisonous'] = True
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session.add(shrew)
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session.flush()
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q = (session.query(Animal).
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filter(Animal.facts.any(
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and_(AnimalFact.key == u'weasel-like',
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AnimalFact.value == True))))
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print('weasel-like animals', q.all())
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.. autosource::
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"""
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