blocks|key|4640868|text|转发我们论坛上的答案，以帮助其他有类似问题的人：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4640869|@connection+=+ActiveRecord::Base.connection
result+=+@connection.exec_query('select+tablename+from+system.tables')
result.each+do+%7Crow%7C
puts+row
end|code-block|syntax|javascript|4640870|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Reposting the answer from our forum to help others with a similar issue:

<pre><code>@connection = ActiveRecord::Base.connection
result = @connection.exec_query('select tablename from system.tables')
result.each do |row|
puts row
end
</code></pre>

blocks|key|134496|text|我用来执行自定义SQL语句的工作命令是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|134497|results+=+ActiveRecord::Base.connection.execute("foo")|code-block|syntax|javascript|134498|其中"foo“是sql语句(即"SELECT+*+FROM+table")。|134499|此命令将以散列的形式返回一组值，并将它们放入结果变量中。|134500|因此，在我的rails+application_controller.rb上，我添加了以下内容：|134501|def+execute_statement(sql)
++results+=+ActiveRecord::Base.connection.execute(sql)

++if+results.present?
++++return+results
++else
++++return+nil
++end
end|134502|使用execute_statement将返回找到的记录，如果没有记录，则返回nil。|134503|这样，我就可以在rails应用程序的任何地方调用它，例如：|134504|records+=+execute_statement("select+*+from+table")|134505|"execute_statement“还可以调用NuoDB过程、函数和数据库视图。|134506|entityMap^0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|12|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|14|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|15|8|@]|9|@]|A|$]]|$1|S|3|T|5|D|7|16|8|@]|9|@]|A|$E|F]]|$1|U|3|V|5|6|7|17|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|X|$]]

The working command I'm using to execute custom SQL statements is:

<pre><code>results = ActiveRecord::Base.connection.execute("foo")
</code></pre>

with "foo" being the sql statement( i.e. "SELECT * FROM table").

This command will return a set of values as a hash and put them into the results variable.

So on my rails application_controller.rb I added this:

<pre><code>def execute_statement(sql)
 results = ActiveRecord::Base.connection.execute(sql)

 if results.present?
 return results
 else
 return nil
 end
end
</code></pre>

Using execute_statement will return the records found and if there is none, it will return nil.

This way I can just call it anywhere on the rails application like for example:

<pre><code>records = execute_statement("select * from table")
</code></pre>

"execute_statement" can also call NuoDB procedures, functions, and also Database Views.

blocks|key|134580|text|对我来说，我不能让它返回一个哈希值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|134581|results+=+ActiveRecord::Base.connection.execute(sql)|code-block|syntax|javascript|134582|但是使用exec_query方法是可行的。|134583|results+=+ActiveRecord::Base.connection.exec_query(sql)|134584|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

For me, I couldn't get this to return a hash.

<pre><code>results = ActiveRecord::Base.connection.execute(sql)
</code></pre>

But using the exec_query method worked.

<pre><code>results = ActiveRecord::Base.connection.exec_query(sql)
</code></pre>

blocks|key|134639|text|一旦您获得MySql::Result对象|type|unstyled|depth|inlineStyleRanges|entityRanges|data|134640|results+=+ActiveRecord::Base.connection.execute(query)|code-block|syntax|javascript|134641|您可以将其转换为行数组|134642|results.to_a|134643|将生成此格式的数组|134644|[[row1][row2]...]|134645|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Once you get the MySql::Result object
<pre><code>results = ActiveRecord::Base.connection.execute(query)
</code></pre>
You can convert it to array of rows
<pre><code>results.to_a
</code></pre>
will make array of this format
<pre><code>[[row1][row2]...]
</code></pre>

I'm trying to manually execute SQL commands so I can access procedures in NuoDB.

I'm using Ruby on Rails and I'm using the following command:

<pre><code>ActiveRecord::Base.connection.execute("SQL query")
</code></pre>

The "SQL query" could be any SQL command.

Like for example I have a table called "Feedback" and when I execute the command:

<pre><code>ActiveRecord::Base.connection.execute("SELECT `feedbacks`.* FROM `feedbacks`")
</code></pre>

This would only return a "true" response instead of sending me all the data requested. 

This is the output on the Rails Console is:

<pre><code>SQL (0.4ms) SELECT `feedbacks`.* FROM `feedbacks`
 =&gt; true
</code></pre>

I would like to use this to call stored procedures in NuoDB but upon calling the procedures, this would also return a "true" response.

Is there anyway I can execute SQL commands and get the data requested instead of getting a "true" response?

How do you manually execute SQL commands in Ruby On Rails using NuoDB

数据库

我正在尝试手动执行SQL命令，这样我就可以访问NuoDB中的过程。我使用Ruby on Rails，并使用以下命令：ActiveRecord::Base.connection.execute("SQL query")"SQL查询“可以是任何SQL命令。例如，我有一个名为"Feedback“的表，当我执行以下命令时：Ac...

问如何使用NuoDB在Ruby On Rails中手动执行SQL命令
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