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Update one MySQL table with values from another
I'm trying to update one MySQL table based on information from another.
2 Answers
2
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Find rows that have the same value on a column in MySQL
... created what was essentially infinite recursion or something on mysql resulting in a dead database due to "too many connections" :-/
– huygir
Mar 5 '18 at 17:40
add...
SQL query return data from multiple tables
...mply a color listing so that we know what colors we have in the car yard.
mysql> create table colors(id int(3) not null auto_increment primary key,
-> color varchar(15), paint varchar(10));
Query OK, 0 rows affected (0.01 sec)
mysql> show columns from colors;
+-------+-------------+-...
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 to prepend a string to a column value in MySQL?
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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...
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...
一个故事告诉你比特币的原理及运作机制 - 创意 - 清泛网 - 专注C/C++及内核技术
...这样以物易物实在太不方便了，于是村子全员开会，讨论如何解决这个问题。有人提议，以便于分割且稀有的东西，例如黄金，作为一般等价物，把其它物品和黄金的对应关系编成一张表格，例如一克黄金对应一只羊，一克黄金...
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...
Replace Default Null Values Returned From Left Outer Join
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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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