大约有 7,000 项符合查询结果(耗时:0.0280秒) [XML]

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How to prepend a string to a column value in MySQL?

... Many string update functions in MySQL seems to be working like this: If one argument is null, then concatenation or other functions return null too. So, to update a field with null value, first set it to a non-null value, such as '' For example: update ta...
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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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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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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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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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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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C++特化模板函数的符号多重定义错误问题 - C/C++ - 清泛网 - 专注C/C++及内核技术

....h 中,结果出现特化模板函数的符号多重定义错误。我要如何组织头文件才能避免多重符号定义错误?我用 /FORCE:MULTIPLE,但我想用一个更好的解决方法。 Lee Kyung Jun 实际上,确实用更好的解决方法。稍后我会解释,但首先让我...
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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 ~...