Changes between Version 3 and Version 4 of Transakcii


Ignore:
Timestamp:
02/12/26 00:40:45 (12 days ago)
Author:
213192
Comment:

--

Legend:

Unmodified
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  • Transakcii

    v3 v4  
    3232SELECT highest_market_value_in_eur
    3333FROM players
    34 WHERE player_id = 26;
     34WHERE player_id = 65;
    3535UPDATE players
    3636SET highest_market_value_in_eur = 7000000
    37 WHERE player_id = 26;
     37WHERE player_id = 65;
    3838
    3939COMMIT;
     
    4242SELECT highest_market_value_in_eur
    4343FROM players
    44 WHERE player_id = 26;
     44WHERE player_id = 65;
    4545
    4646COMMIT;
     
    5454SELECT highest_market_value_in_eur
    5555FROM players
    56 WHERE player_id = 26;
     56WHERE player_id = 65;
    5757
    5858UPDATE players 
    59 SET highest_market_value_in_eur = 9000000 
    60 WHERE player_id = 26
     59SET highest_market_value_in_eur = 70000000
     60WHERE player_id = 65
    6161
    6262COMMIT; 
     
    6464SELECT highest_market_value_in_eur
    6565FROM players
    66 WHERE player_id = 26;
     66WHERE player_id = 65;
    6767
    6868COMMIT;
     
    7777{{{
    7878BEGIN; 
    79 SELECT * FROM players WHERE player_id = 10 FOR UPDATE; 
    80 SELECT * FROM players WHERE player_id = 20 FOR UPDATE; 
     79SELECT * FROM players WHERE player_id = 65 FOR UPDATE; 
     80SELECT * FROM players WHERE player_id = 80 FOR UPDATE; 
    8181COMMIT;
    8282
    8383BEGIN;
    84 SELECT * FROM players WHERE player_id = 20 FOR UPDATE;
    85 SELECT * FROM players WHERE player_id = 10 FOR UPDATE;
     84SELECT * FROM players WHERE player_id = 80 FOR UPDATE;
     85SELECT * FROM players WHERE player_id = 65 FOR UPDATE;
    8686COMMIT;
    8787}}}
     
    9494SELECT * FROM players
    9595
    96 WHERE player_id IN (10, 20)
     96WHERE player_id IN (65, 80)
    9797
    9898ORDER BY player_id
     
    133133BEGIN;
    134134
    135 SELECT * FROM players WHERE player_id = 1 FOR UPDATE;
     135SELECT * FROM players WHERE player_id = 65 FOR UPDATE;
    136136
    137137-- само редот со id=1 е заклучен
    138138
    139 SELECT * FROM players WHERE player_id = 2;
     139SELECT * FROM players WHERE player_id = 80;
    140140
    141141-- работи нормално
    142142
    143 UPDATE players SET highest_market_value_in_eur = highest_market_value_in_eur - 100 WHERE player_id = 1;
     143UPDATE players SET highest_market_value_in_eur = highest_market_value_in_eur - 100 WHERE player_id = 65;
    144144
    145145-- чека, редот е заклучен
     
    156156UPDATE players
    157157SET market_value_in_eur = market_value_in_eur - 5000000
    158 WHERE player_id = 19054;
     158WHERE player_id = 65;
    159159
    160160-- трансакцијата е започната, но не е направен COMMIT
     
    165165SELECT market_value_in_eur
    166166FROM players
    167 WHERE player_id = 19054;
     167WHERE player_id = 65;
    168168-- Session 2 ја гледа старата вредност
    169169}}}
     
    178178SELECT market_value_in_eur
    179179FROM players
    180 WHERE player_id = 19054;
     180WHERE player_id = 65;
    181181-- сега Session 2 ја гледа новата вредност
    182182}}}