大约有 1,948 项符合查询结果（耗时：0.0185秒） [XML]
How to change the output color of echo in Linux
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Anywhere that has a tty interpreter
xterm, gnome-terminal, kde-terminal, mysql-client-CLI and so on.
For example if you want to colorize your output with mysql you can use Perl
#!/usr/bin/perl -n
print "\033[1m\033[31m$1\033[36m$2\033[32m$3\033[33m$4\033[m" while /([|+-]+)|([0-9]+)|([a-zA-Z_]+)|([...
How to get last inserted id?
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I'm coming from a mysql background, I can't understand this command: Int32 newId = (Int32) myCommand.ExecuteScalar();
– Naguib Ihab
May 28 '15 at 1:23
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Does a UNIQUE constraint automatically create an INDEX on the field(s)?
...email, user_id) is enough, you don't need a separate index on email only - MySQL can use leftmost parts of a composite index. There may be some border cases where the size of an index can slow down your queries, but you should not worry about them until you actually run into them.
As for testing in...
Does Foreign Key improve query performance?
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foreign keys do improve performance, at least in MySQL. Moreover, you're right, the creation of a FK does not create an index; the creation of a FK requires an index
– Félix Gagnon-Grenier
Aug 26 '14 at 17:31
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Database Structure for Tree Data Structure
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Have a look at Managing Hierarchical Data in MySQL. It discusses two approaches for storing and managing hierarchical (tree-like) data in a relational database.
The first approach is the adjacency list model, which is what you essentially describe: having a foreign key...
Update all values of a column to lowercase
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See http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_lower
UPDATE table_name SET tag = LOWER(tag)
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How to host a Node.Js application in shared hosting [closed]
... 30 minutes to set up the configuration, and it'll work with npm, Express, MySQL, etc.
See a2hosting.com.
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Why should I capitalize my SQL keywords? [duplicate]
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So does MySQL, and for good and for bad (mostly bad:-), many developers first exposure to SQL is through MySQL.
– Paul Tomblin
Mar 4 '09 at 13:41
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Sqlite LIMIT / OFFSET query
...T <count> OFFSET <skip>
It's compatible with the syntax from MySQL and PostgreSQL. MySQL supports both syntax forms, and its docs claim that the second syntax with OFFSET was meant to provide compatibility with PostgreSQL. PostgreSQL docs show it only supports the second syntax, and ...
String concatenation does not work in SQLite
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Oracle CONCAT(string1, string2) or ||
MySQL CONCAT(string1, string2, string3...) or || if PIPES_AS_CONCAT enabled
Postgres CONCAT(string1, string2, string3...) or ||
Microsoft SQL Server 2012+ CONCAT(string1, string2, str...