mysql> SELECT
    ->   LEFT(rc_timestamp, 10) AS hour,
    ->   COUNT(rc_timestamp) AS users
    -> FROM recentchanges
    -> WHERE rc_log_type = 'newusers'
    -> GROUP BY hour;
+------------+-------+
| hour       | users |
+------------+-------+
| 2011092113 |     3 |
| 2011092114 |     2 |
| 2011092115 |     4 |
| 2011092116 |     2 |
| 2011092117 |     1 |
| 2011092118 |     1 |
| 2011092121 |     1 |
| 2011092122 |     2 |
| 2011092123 |     1 |
| 2011092200 |     1 |
| 2011092201 |     1 |
| 2011092202 |     1 |
| 2011092203 |     1 |
| 2011092204 |     2 |
| 2011092206 |     2 |
| 2011092207 |     3 |
| 2011092208 |     1 |
| 2011092209 |     3 |
| 2011092210 |     2 |
| 2011092211 |     5 |
| 2011092212 |     1 |
| 2011092213 |     2 |
| 2011092214 |     3 |
| 2011092215 |     3 |
| 2011092216 |     5 |
| 2011092217 |     1 |
| 2011092219 |     1 |
| 2011092220 |     2 |
| 2011092221 |     2 |
| 2011092222 |     2 |
| 2011092223 |     2 |
| 2011092301 |     1 |
| 2011092302 |     1 |
| 2011092303 |     2 |
| 2011092305 |     1 |
| 2011092306 |     1 |
| 2011092308 |     2 |
| 2011092309 |     3 |
| 2011092310 |     4 |
| 2011092311 |     1 |
| 2011092312 |     2 |
| 2011092314 |     1 |
| 2011092316 |     2 |
| 2011092318 |     2 |
| 2011092320 |     3 |
| 2011092321 |     3 |
| 2011092400 |     1 |
| 2011092405 |     3 |
| 2011092407 |     1 |
| 2011092408 |     1 |
| 2011092410 |     2 |
| 2011092412 |     2 |
| 2011092413 |     2 |
| 2011092414 |     1 |
| 2011092415 |     1 |
| 2011092416 |     2 |
| 2011092417 |     1 |
| 2011092418 |     1 |
| 2011092420 |     1 |
| 2011092421 |     1 |
| 2011092422 |     1 |
| 2011092502 |     2 |
| 2011092503 |     1 |
| 2011092504 |     2 |
| 2011092506 |     1 |
| 2011092507 |     1 |
| 2011092508 |     1 |
| 2011092511 |     1 |
| 2011092513 |     1 |
| 2011092514 |     1 |
| 2011092515 |     1 |
| 2011092516 |     4 |
| 2011092518 |     2 |
| 2011092519 |     2 |
| 2011092520 |     1 |
| 2011092521 |     1 |
| 2011092522 |     2 |
| 2011092600 |     1 |
| 2011092602 |     2 |
| 2011092604 |     1 |
| 2011092605 |     2 |
| 2011092606 |     3 |
| 2011092607 |     2 |
| 2011092608 |     4 |
| 2011092609 |     1 |
| 2011092610 |     2 |
| 2011092612 |     1 |
| 2011092613 |     4 |
| 2011092614 |     1 |
| 2011092615 |     2 |
| 2011092616 |     3 |
| 2011092617 |     3 |
| 2011092618 |     1 |
| 2011092620 |     2 |
| 2011092622 |     1 |
| 2011092700 |     1 |
| 2011092701 |     3 |
| 2011092703 |     5 |
| 2011092704 |     2 |
| 2011092705 |     2 |
| 2011092706 |     2 |
| 2011092707 |     1 |
| 2011092708 |     1 |
| 2011092709 |     2 |
| 2011092710 |     3 |
| 2011092711 |     1 |
| 2011092712 |     1 |
| 2011092713 |     4 |
| 2011092714 |     4 |
| 2011092715 |     6 |
| 2011092716 |     2 |
| 2011092717 |     1 |
| 2011092718 |     2 |
| 2011092719 |     1 |
| 2011092721 |     3 |
| 2011092723 |     3 |
| 2011092804 |     2 |
| 2011092805 |     1 |
| 2011092806 |     3 |
| 2011092807 |     2 |
| 2011092808 |     2 |
| 2011092809 |     1 |
| 2011092810 |     1 |
| 2011092811 |     1 |
| 2011092812 |     1 |
| 2011092813 |     2 |
| 2011092814 |     3 |
| 2011092815 |     1 |
| 2011092816 |     3 |
| 2011092818 |     1 |
| 2011092819 |     2 |
| 2011092820 |     2 |
| 2011092821 |     1 |
| 2011092822 |     2 |
| 2011092900 |     2 |
| 2011092901 |     1 |
| 2011092906 |     2 |
| 2011092907 |     3 |
| 2011092908 |     2 |
| 2011092909 |     2 |
| 2011092910 |     3 |
| 2011092912 |     2 |
| 2011092914 |     2 |
| 2011092915 |     1 |
| 2011092916 |     2 |
| 2011092917 |     1 |
| 2011092918 |     1 |
| 2011092919 |     1 |
| 2011092921 |     1 |
| 2011092922 |     2 |
| 2011092923 |     1 |
| 2011093002 |     1 |
| 2011093004 |     1 |
| 2011093006 |     2 |
| 2011093007 |     2 |
| 2011093009 |     1 |
| 2011093010 |     3 |
| 2011093011 |     1 |
| 2011093012 |     1 |
| 2011093013 |     3 |
| 2011093014 |     1 |
| 2011093015 |     1 |
| 2011093016 |     4 |
| 2011093017 |     1 |
| 2011093018 |     2 |
| 2011093020 |     3 |
| 2011093021 |     3 |
| 2011093023 |     2 |
| 2011100100 |     1 |
| 2011100101 |     2 |
| 2011100102 |     1 |
| 2011100103 |     2 |
| 2011100108 |     3 |
| 2011100109 |     2 |
| 2011100112 |     1 |
| 2011100113 |     2 |
| 2011100114 |     2 |
| 2011100116 |     2 |
| 2011100118 |     1 |
| 2011100119 |     1 |
| 2011100200 |     1 |
| 2011100203 |     3 |
| 2011100209 |     1 |
| 2011100210 |     2 |
| 2011100213 |     1 |
| 2011100215 |     1 |
| 2011100216 |     4 |
| 2011100217 |     1 |
| 2011100218 |     2 |
| 2011100219 |     4 |
| 2011100220 |     2 |
| 2011100221 |     1 |
| 2011100222 |     3 |
| 2011100302 |     1 |
| 2011100306 |     2 |
| 2011100307 |     1 |
| 2011100308 |     4 |
| 2011100309 |     3 |
| 2011100310 |     2 |
| 2011100311 |     1 |
| 2011100312 |     2 |
| 2011100313 |     2 |
| 2011100314 |     2 |
| 2011100315 |     6 |
| 2011100316 |     1 |
| 2011100317 |     3 |
| 2011100318 |     4 |
| 2011100319 |     4 |
| 2011100320 |     1 |
| 2011100321 |     2 |
| 2011100323 |     1 |
| 2011100403 |     1 |
| 2011100404 |     1 |
| 2011100405 |     3 |
| 2011100407 |     4 |
| 2011100408 |     1 |
| 2011100409 |     1 |
| 2011100410 |     1 |
| 2011100411 |     5 |
| 2011100412 |     5 |
| 2011100413 |     2 |
| 2011100414 |     4 |
| 2011100415 |     2 |
| 2011100416 |     3 |
| 2011100417 |     1 |
| 2011100418 |     4 |
| 2011100419 |     2 |
| 2011100421 |     4 |
| 2011100422 |     3 |
| 2011100423 |     2 |
| 2011100500 |     2 |
| 2011100501 |     1 |
| 2011100502 |     1 |
| 2011100503 |     1 |
| 2011100504 |     2 |
| 2011100505 |     3 |
| 2011100506 |     3 |
| 2011100507 |     1 |
| 2011100508 |     3 |
| 2011100509 |     4 |
| 2011100511 |     2 |
| 2011100512 |     1 |
| 2011100513 |     3 |
| 2011100514 |     1 |
| 2011100515 |     3 |
| 2011100517 |     3 |
| 2011100519 |     1 |
| 2011100520 |     3 |
| 2011100521 |     2 |
| 2011100522 |     1 |
| 2011100601 |     1 |
| 2011100602 |     1 |
| 2011100603 |     3 |
| 2011100605 |     5 |
| 2011100607 |     2 |
| 2011100608 |     3 |
| 2011100609 |     2 |
| 2011100610 |     2 |
| 2011100611 |     4 |
| 2011100612 |     3 |
| 2011100613 |     1 |
| 2011100614 |     2 |
| 2011100615 |     3 |
| 2011100616 |     2 |
| 2011100617 |     3 |
| 2011100618 |     4 |
| 2011100619 |     2 |
| 2011100620 |     2 |
| 2011100621 |     3 |
| 2011100622 |     2 |
| 2011100701 |     1 |
| 2011100702 |     3 |
| 2011100705 |     4 |
| 2011100706 |     1 |
| 2011100707 |     3 |
| 2011100708 |     2 |
| 2011100709 |     1 |
| 2011100710 |     3 |
| 2011100711 |     2 |
| 2011100713 |     3 |
| 2011100714 |     2 |
| 2011100715 |     2 |
| 2011100716 |     2 |
| 2011100717 |     2 |
| 2011100718 |     2 |
| 2011100719 |     3 |
| 2011100720 |     1 |
| 2011100721 |     2 |
| 2011100722 |     4 |
| 2011100723 |     1 |
| 2011100800 |     1 |
| 2011100801 |     1 |
| 2011100802 |     3 |
| 2011100806 |     4 |
| 2011100807 |     3 |
| 2011100808 |     2 |
| 2011100811 |     1 |
| 2011100812 |     1 |
| 2011100813 |     2 |
| 2011100814 |     1 |
| 2011100815 |     1 |
| 2011100816 |     2 |
| 2011100817 |     2 |
| 2011100818 |     1 |
| 2011100819 |     1 |
| 2011100820 |     1 |
| 2011100821 |     2 |
| 2011100822 |     3 |
| 2011100823 |     1 |
| 2011100900 |     1 |
| 2011100902 |     2 |
| 2011100903 |     1 |
| 2011100904 |     2 |
| 2011100905 |     2 |
| 2011100908 |     1 |
| 2011100910 |     2 |
| 2011100911 |     1 |
| 2011100914 |     1 |
| 2011100917 |     2 |
| 2011100918 |     2 |
| 2011100919 |     1 |
| 2011100920 |     1 |
| 2011100921 |     2 |
| 2011100922 |    10 |
| 2011101000 |     2 |
| 2011101002 |     2 |
| 2011101003 |     1 |
| 2011101004 |     3 |
| 2011101005 |     2 |
| 2011101006 |     1 |
| 2011101007 |     5 |
| 2011101009 |     1 |
| 2011101010 |     2 |
| 2011101011 |     5 |
| 2011101013 |     4 |
| 2011101014 |     9 |
| 2011101015 |    11 |
| 2011101017 |     4 |
| 2011101018 |     2 |
| 2011101019 |     1 |
| 2011101020 |     2 |
| 2011101021 |     2 |
| 2011101022 |     2 |
| 2011101023 |     3 |
| 2011101101 |     4 |
| 2011101103 |     1 |
| 2011101104 |     1 |
| 2011101105 |     2 |
| 2011101108 |     2 |
| 2011101109 |     1 |
| 2011101110 |     6 |
| 2011101111 |     1 |
| 2011101112 |     4 |
| 2011101113 |     5 |
| 2011101114 |     1 |
| 2011101115 |     2 |
| 2011101116 |     1 |
| 2011101117 |     3 |
| 2011101118 |     3 |
| 2011101119 |     1 |
| 2011101120 |     3 |
| 2011101122 |     2 |
| 2011101201 |     2 |
| 2011101203 |     1 |
| 2011101206 |     1 |
| 2011101207 |     1 |
| 2011101208 |     1 |
| 2011101209 |     2 |
| 2011101210 |     4 |
| 2011101211 |     3 |
| 2011101212 |     3 |
| 2011101214 |     2 |
| 2011101215 |     1 |
| 2011101216 |     3 |
| 2011101217 |     3 |
| 2011101218 |     1 |
| 2011101219 |     1 |
| 2011101222 |     1 |
| 2011101223 |     2 |
| 2011101302 |     1 |
| 2011101305 |     1 |
| 2011101306 |     4 |
| 2011101308 |     1 |
| 2011101309 |     2 |
| 2011101310 |     2 |
| 2011101311 |     1 |
| 2011101312 |     1 |
| 2011101313 |     3 |
| 2011101314 |     3 |
| 2011101315 |     3 |
| 2011101316 |     5 |
| 2011101317 |     2 |
| 2011101319 |     4 |
| 2011101320 |     1 |
| 2011101321 |     1 |
| 2011101322 |     1 |
| 2011101400 |     1 |
| 2011101401 |     1 |
| 2011101402 |     1 |
| 2011101403 |     1 |
| 2011101406 |     1 |
| 2011101408 |     1 |
| 2011101409 |     2 |
| 2011101411 |     2 |
| 2011101412 |     2 |
| 2011101414 |     4 |
| 2011101415 |     3 |
| 2011101416 |     3 |
| 2011101418 |     1 |
| 2011101419 |     2 |
| 2011101420 |     2 |
| 2011101421 |     1 |
| 2011101501 |     2 |
| 2011101502 |     2 |
| 2011101503 |     1 |
| 2011101504 |     1 |
| 2011101505 |     3 |
| 2011101506 |     1 |
| 2011101507 |     2 |
| 2011101508 |     1 |
| 2011101509 |     1 |
| 2011101510 |     3 |
| 2011101512 |     3 |
| 2011101513 |     2 |
| 2011101514 |     2 |
| 2011101515 |     1 |
| 2011101516 |     3 |
| 2011101519 |     3 |
| 2011101520 |     3 |
| 2011101521 |     1 |
| 2011101522 |     1 |
| 2011101601 |     2 |
| 2011101603 |     1 |
| 2011101604 |     1 |
| 2011101605 |     1 |
| 2011101606 |     1 |
| 2011101607 |     2 |
| 2011101610 |     2 |
| 2011101612 |     1 |
| 2011101613 |     2 |
| 2011101614 |     2 |
| 2011101615 |     2 |
| 2011101616 |     2 |
| 2011101617 |     3 |
| 2011101620 |     2 |
| 2011101623 |     2 |
| 2011101701 |     1 |
| 2011101706 |     1 |
| 2011101707 |     4 |
| 2011101708 |     1 |
| 2011101709 |     5 |
| 2011101711 |     2 |
| 2011101712 |     2 |
| 2011101713 |     1 |
| 2011101714 |     2 |
| 2011101715 |     2 |
| 2011101716 |     3 |
| 2011101717 |     1 |
| 2011101718 |     1 |
| 2011101719 |     5 |
| 2011101720 |     1 |
| 2011101722 |     2 |
| 2011101723 |     2 |
| 2011101801 |     1 |
| 2011101804 |     1 |
| 2011101805 |     2 |
| 2011101807 |     2 |
| 2011101808 |     3 |
| 2011101810 |     1 |
| 2011101812 |     4 |
| 2011101813 |     1 |
| 2011101814 |     2 |
| 2011101815 |     3 |
| 2011101816 |     1 |
| 2011101817 |     3 |
| 2011101818 |     4 |
| 2011101819 |     3 |
| 2011101820 |     2 |
| 2011101821 |     1 |
| 2011101823 |     2 |
| 2011101900 |     3 |
| 2011101902 |     2 |
| 2011101903 |     3 |
| 2011101904 |     1 |
| 2011101905 |     3 |
| 2011101906 |     1 |
| 2011101907 |     3 |
| 2011101908 |     4 |
| 2011101909 |     1 |
| 2011101910 |     2 |
| 2011101911 |     1 |
| 2011101912 |     2 |
| 2011101914 |     5 |
| 2011101915 |     8 |
| 2011101916 |     2 |
| 2011101918 |     4 |
| 2011101919 |     4 |
| 2011101920 |     1 |
| 2011101921 |     1 |
| 2011101922 |     6 |
| 2011101923 |     5 |
| 2011102000 |     2 |
| 2011102001 |     1 |
| 2011102002 |     2 |
| 2011102003 |     2 |
| 2011102005 |     1 |
| 2011102006 |     3 |
| 2011102007 |     6 |
| 2011102008 |     1 |
| 2011102009 |     6 |
| 2011102010 |     1 |
| 2011102011 |     2 |
| 2011102012 |     2 |
| 2011102014 |     2 |
| 2011102015 |     5 |
| 2011102016 |     1 |
| 2011102017 |     4 |
| 2011102018 |     5 |
| 2011102019 |     1 |
| 2011102020 |     1 |
| 2011102021 |     1 |
| 2011102022 |     3 |
| 2011102023 |     1 |
| 2011102100 |     3 |
| 2011102101 |     9 |
| 2011102102 |    35 |
| 2011102103 |    35 |
| 2011102104 |    37 |
| 2011102105 |    29 |
| 2011102106 |    49 |
| 2011102107 |    39 |
| 2011102108 |    38 |
| 2011102109 |    37 |
| 2011102110 |    41 |
| 2011102111 |    40 |
| 2011102112 |    33 |
+------------+-------+
536 rows in set (0.01 sec)