Query Mode

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Revision as of 12:26, 10 January 2011 by AW (talk | contribs) (→‎Python Example)
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In the query mode a query can be send to the server and executed in an iterative manner. For this you have to call the query() function of the Session with your defined query. This will return a query object which comes with an forward-only iterator to get each result of the query. Furthermore it is possible to bind variables to the query using the bind() function of the query object.

Usage

The query execution works as follows:

  1. Create a new session instance with hostname, port, username and password.
  2. Call the query() function of the session with the query as argument to get your query object.
  3. Optionally bind variables to the query with the bind() function.
  4. Initialize query output via init().
  5. Iterate through the query object with the more() and next() functions. If an error occurs, an exception is thrown.
  6. Close the query with close().

Example in PHP

import BaseXClient, time

try:
  # initialize timer
  start = time.clock()

  # create session
  session = BaseXClient.Session('localhost', 1984, 'admin', 'admin')

  # perform command and print returned string
  print session.execute("xquery 1 to 10")

  # close session
  session.close()

  # print time needed
  time = (time.clock() - start) * 1000
  print time, "ms."

except IOError as e:
  # print exception
  print e

for more examples see the languages section.