ngamsPlotFilesizeDist.py 文件源码

def queryDb(db='Pawsey', limit=None, saveToCSV=None):
    """
    Return the query result as a numpy array

    saveToCSV:  csv file name (string)
    """
    if (not DB.has_key(db)):
        raise Exception("Unknown db name {0}".format(db))
    # don't want to use group by to relief the database
    if (limit is None or len(limit) == 0):
        sl = ""
    else:
        sl = " {0}".format(limit)
    hsql = "select file_size from ngas_files {0}".format(sl)
    try:
        t = dbpass
    except NameError:
        dbpass = getpass.getpass('%s DB password: ' % db)
        print "Connecting to DB"
        dbconn = dbdrv.connect(database="ngas", user="ngas_ro",
                             password=dbpass, host=DB[db])

    cur = dbconn.cursor()
    print "Executing query '{0}'".format(hsql)
    cur.execute(hsql)
    r = cur.fetchall()
    dbconn.close()
    del(dbconn)
    res = pylab.array(r)
    ll = len(res)
    res = res[:,0].reshape(ll)
    if (not (saveToCSV is None)):
        f = open(saveToCSV, 'wb')
        for li in res:
            #print "--{0}:{1}".format(int(li), type(int(li)))
            f.write("{0}\n".format(li))

    return res # get the first (only) column from all rows