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MySQL, better to insert NULL or empty string?
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One thing to consider, if you ever plan on switching databases, is that Oracle does not support empty strings. They are converted to NULL automatically and you can't query for them using clauses like WHERE somefield = '' .
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What is the Oracle equivalent of SQL Server's IsNull() function?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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GROUP_CONCAT ORDER BY
...MySQL only function, however a similar result can be achieved on other database with a surrogate function ...
– aleroot
Apr 30 '15 at 20:41
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How to write multiple line property value using PropertiesConfiguration?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How many characters can UTF-8 encode?
... always uses 2 bytes, but UTF-8 uses one byte per character for most latin-based language characters. Making it twice as compact.
– sanderd17
Mar 25 '19 at 8:17
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must appear in the GROUP BY clause or be used in an aggregate function
...s, ordered by avg, and returns the first element (arrays in postgres are 1-based).
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Best practices for storing postal addresses in a database (RDBMS)?
... use, one schema to consider is the one used by Drupal Address Field. It's based on the xNAL standard, and seems to cover most international cases. A bit of digging into that module will reveal some nice pearls for interpreting and validating addresses internationally. It also has a nice set of admi...
Regex how to match an optional character
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Practical uses for AtomicInteger
...() as a type of optimistic locking - get the current value, compute result based on this, set this result iff value is still the input used to do the calculation, else start again - but the counting examples are very useful, and I'll often use AtomicIntegers for counting and VM-wide unique generator...
Find the extension of a filename in Ruby
...orks for multi-period suffixes, except an heuristic (thus error prone) database of extensions.
– Ciro Santilli 郝海东冠状病六四事件法轮功
Oct 24 '14 at 14:10
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