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json_encode is returning NULL?

... few day ago I have the SAME problem with 1 table. Firstly try: echo json_encode($rows); echo json_last_error(); // returns 5 ? If last line returns 5, problem is with your data. I know, your tables are in UTF-8, but not entered data. For example the input was i...
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belongs_to through associations

...ter off caching the question_id on Choice and adding a unique index to the table (especially because validates_uniqueness_of is prone to race conditions). If you're paranoid, add a custom validation to Choice that confirms that the answer's question_id matches, but it sounds like the end user shoul...
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How do I center floated elements?

...g floats is easy. Just use the style for container: .pagination{ display: table; margin: 0 auto; } change the margin for floating elements: .pagination a{ margin: 0 2px; } or .pagination a{ margin-left: 3px; } .pagination a.first{ margin-left: 0; } and leave the rest as it is. It's the be...
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TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT maximum storage sizes

...set-unicode-utf8.html, max 3 bytes for utf-8. THIS IS A ROUGH ESTIMATION TABLE FOR QUICK DECISIONS! So the worst case assumptions (3 bytes per utf-8 char) to best case (1 byte per utf-8 char) Assuming the english language has an average of 4.5 letters per word x is the number of bytes allocated ...
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Interfaces — What's the point?

...alled "Order", whereas if you make the call to a C# object, it's already established that it implements that method, and the call can be made to such an such address. – Boluc Papuccuoglu May 11 '13 at 15:16 ...
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Why use the INCLUDE clause when creating an index?

...nd that get used a lot), it can be very helpful to INCLUDE those into a suitable non-clustered index. share | improve this answer | follow | ...
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PostgreSQL delete with inner join

... for larger tables, the first solution in this answer is potentially much faster. – mgoldwasser Nov 2 '14 at 16:58 2 ...
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What is a simple command line program or script to backup SQL server databases?

...tructure to access MSSQL databases. Here's a simple shell script to dump a table to a file: #!/usr/bin/ksh # #..... ( tsql -S {database} -U {user} -P {password} <<EOF select * from {table} go quit EOF ) >{output_file.dump} ...
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Simulate low network connectivity for Android [closed]

... Set network latency emulation to . Default value is none. See the table in Network Delay Emulation for supported values. -netspeed <speed> Set network speed emulation to . Default value is full. See the table in Network Speed Emulation for supported values. Speeds for re...
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position: fixed doesn't work on iPad and iPhone

...s.html (but note that the mobile browser world is moving very quickly, so tables like this may not stay up-to-date for long!) Update: iOS 5 and Android 4 are both reported to have position:fixed support now. I tested iOS 5 myself in an Apple store today and can confirm that it does work with pos...