Will a mysql table lock wait or return an error if another process has the table;











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If I have one script (B) that is writing to a MySQL table without a lock and another script (A) tries to get a lock on that table at the very same moment, what happens?



Will Script A immediately return an (unable to lock error), or will it hang till it either gets the lock or exceeds the time_out default?



Thanks.



Script A



lock tables mytable write;

...do some reading....

...do some writing....

unlock tables;


Script B



...do some writing without a lock....





mysql







share|improve this question


























    up vote
    0
    down vote

    favorite












    If I have one script (B) that is writing to a MySQL table without a lock and another script (A) tries to get a lock on that table at the very same moment, what happens?



    Will Script A immediately return an (unable to lock error), or will it hang till it either gets the lock or exceeds the time_out default?



    Thanks.



    Script A



    lock tables mytable write;
    
...do some reading....
    
...do some writing....
    
unlock tables;


    Script B



    ...do some writing without a lock....





    mysql







    share|improve this question
























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      If I have one script (B) that is writing to a MySQL table without a lock and another script (A) tries to get a lock on that table at the very same moment, what happens?



      Will Script A immediately return an (unable to lock error), or will it hang till it either gets the lock or exceeds the time_out default?



      Thanks.



      Script A



      lock tables mytable write;
      
...do some reading....
      
...do some writing....
      
unlock tables;


      Script B



      ...do some writing without a lock....





      mysql







      share|improve this question













      If I have one script (B) that is writing to a MySQL table without a lock and another script (A) tries to get a lock on that table at the very same moment, what happens?



      Will Script A immediately return an (unable to lock error), or will it hang till it either gets the lock or exceeds the time_out default?



      Thanks.



      Script A



      lock tables mytable write;
      
...do some reading....
      
...do some writing....
      
unlock tables;


      Script B



      ...do some writing without a lock....





      mysql




      mysql






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 22 at 2:49









      Sergio D. Caplan

      176110




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