大约有 7,000 项符合查询结果(耗时:0.0216秒) [XML]

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Is there documentation for the Rails column types?

...ded by Rails mostly for compatibility with database systems. For instance, MySQL's TIMESTAMP datatype is stored as a unix timestamp. Its valid range goes from 1970 to 2038, and the time is stored as the number of seconds that have elapsed since the last epoch, which is supposedly standard, but in pr...
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Real escape string and PDO [duplicate]

I'm using PDO after migrating away from the mysql library. What do I use in place of the old real_escape_string function? ...
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How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio

...e->timestamp('created_at')->useCurrent(); Back to the question, on MySQL you could also use the ON UPDATE clause through DB::raw(): $table->timestamp('updated_at')->default(DB::raw('CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP')); Gotchas MySQL Starting with MySQL 5.7, 0000-00-00...
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Replace Default Null Values Returned From Left Outer Join

... If it is MySQL, IsNull should be replaced with 'IFNULL'. Thanks. – Dhanushka Jul 14 '14 at 6:54 ...
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一文了解大数据领域创业的机会与方向 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术

...据告诉我们,究竟什么是大数据,大数据行业的创业机会如何,未来的创业方向又有哪些。 接触大数据,了解这个行业已经有两年多了,每天都在阅读大量的关于大数据的文献资料和技术文章。如果你要问我什么是大数据?以...
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MySQL search and replace some text in a field

What MySQL query will do a text search and replace in one particular field in a table? 7 Answers ...
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MySQL: multiple tables or one table with many columns?

... Recently I was faced with this same problem, because MySQL InnoDB tables have a relatively small length limit (~8000 bytes). In my problem table (data from very lengthy insurance forms, more than 100 columns) we have multiple varchar columns, all UTF8. So we easily filled the ~...
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What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]

I've got two options for unicode that look promising for a mysql database. 2 Answers 2...
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How do I query between two dates using MySQL?

... DATE() is a MySQL function that extracts only the date part of a date or date/time expression SELECT * FROM table_name WHERE DATE(date_field) BETWEEN '2016-12-01' AND '2016-12-10'; ...
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Differences between utf8 and latin1

...w a bit Java). Note that full 4-byte UTF-8 support was only introduced in MySQL 5.5. Before that version, it only goes up to 3 bytes per character, not 4 bytes per character. So, it supported only the BMP plane and not e.g. the Emoji plane. If you want full 4-byte UTF-8 support, upgrade MySQL to at...