title: How to create a temporary table for an existing table with sqlalchemy?
body: <p>I have a table(in mysql-server) associated with the following class:</p>
  
  <pre><code>class Number(Base):
      __table_name__ = 'number'
      col0 = Column(...) # PRIMARY KEY
      col1 = Column(...)
      col2 = Column(...)
      col3 = Column(...)
  </code></pre>
  
  <p>I want to create a temporary table for this number table when the program starts, this temporary table looks like:</p>
  
  <pre><code>class tempNumber(Base):
        __table_name__ = 'temp_number'
        col0 = Column(...) # direct from Number.col0
        col1 = Column(...) # from Number.col1, but will be modified, for example tempNumber.col1 = Number.col1.replace(' ','')
  </code></pre>
  
  <p>I also tried  to add the following line to class Number:</p>
  
  <pre><code>__table_args__ = {'prefixes': ['TEMPORARY']}
  </code></pre>
  
  <p>but my python programm told me that table temp_number doesn't exist.</p>
  
  <p>and one more question is, how to copy the data fast? because there are lots of rows in table number.</p>