SQLiteDatabase DROP TABLE IF EXISTS not working












-1














Situation

I need to delete all entries of a specific Table in the database so i figured i would just drop it.



DROP TABLE IF EXISTS LogEntry


I tried running the sql using SQLiteDatabase#execSql(String) and SQLiteDatabase#rawQuery(String, String). I start a transaction before execution it and end it after executing it using SQLiteDatabase#beginTransaction() and SQLiteDatabase#endTransaction().



Problem

In both cases the SQL executed without throwing an Exception but the table still exists. I ran a SELECT Statement right after the drop to see if it worked and it had the same results as before the drop.










share|improve this question




















  • 1




    Why not just delete from LogEntry. Then you don't need to recreate it
    – juergen d
    Nov 21 at 10:17










  • @juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
    – Basti
    Nov 21 at 10:36










  • beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
    – Fantômas
    Nov 21 at 10:53












  • Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
    – laalto
    Nov 21 at 11:20










  • @Basti You have change your database version ?
    – Hardik Parmar
    Nov 21 at 16:48
















-1














Situation

I need to delete all entries of a specific Table in the database so i figured i would just drop it.



DROP TABLE IF EXISTS LogEntry


I tried running the sql using SQLiteDatabase#execSql(String) and SQLiteDatabase#rawQuery(String, String). I start a transaction before execution it and end it after executing it using SQLiteDatabase#beginTransaction() and SQLiteDatabase#endTransaction().



Problem

In both cases the SQL executed without throwing an Exception but the table still exists. I ran a SELECT Statement right after the drop to see if it worked and it had the same results as before the drop.










share|improve this question




















  • 1




    Why not just delete from LogEntry. Then you don't need to recreate it
    – juergen d
    Nov 21 at 10:17










  • @juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
    – Basti
    Nov 21 at 10:36










  • beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
    – Fantômas
    Nov 21 at 10:53












  • Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
    – laalto
    Nov 21 at 11:20










  • @Basti You have change your database version ?
    – Hardik Parmar
    Nov 21 at 16:48














-1












-1








-1







Situation

I need to delete all entries of a specific Table in the database so i figured i would just drop it.



DROP TABLE IF EXISTS LogEntry


I tried running the sql using SQLiteDatabase#execSql(String) and SQLiteDatabase#rawQuery(String, String). I start a transaction before execution it and end it after executing it using SQLiteDatabase#beginTransaction() and SQLiteDatabase#endTransaction().



Problem

In both cases the SQL executed without throwing an Exception but the table still exists. I ran a SELECT Statement right after the drop to see if it worked and it had the same results as before the drop.










share|improve this question















Situation

I need to delete all entries of a specific Table in the database so i figured i would just drop it.



DROP TABLE IF EXISTS LogEntry


I tried running the sql using SQLiteDatabase#execSql(String) and SQLiteDatabase#rawQuery(String, String). I start a transaction before execution it and end it after executing it using SQLiteDatabase#beginTransaction() and SQLiteDatabase#endTransaction().



Problem

In both cases the SQL executed without throwing an Exception but the table still exists. I ran a SELECT Statement right after the drop to see if it worked and it had the same results as before the drop.







android database sqlite






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share|improve this question













share|improve this question




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edited Nov 22 at 7:09

























asked Nov 21 at 10:15









Basti

423317




423317








  • 1




    Why not just delete from LogEntry. Then you don't need to recreate it
    – juergen d
    Nov 21 at 10:17










  • @juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
    – Basti
    Nov 21 at 10:36










  • beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
    – Fantômas
    Nov 21 at 10:53












  • Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
    – laalto
    Nov 21 at 11:20










  • @Basti You have change your database version ?
    – Hardik Parmar
    Nov 21 at 16:48














  • 1




    Why not just delete from LogEntry. Then you don't need to recreate it
    – juergen d
    Nov 21 at 10:17










  • @juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
    – Basti
    Nov 21 at 10:36










  • beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
    – Fantômas
    Nov 21 at 10:53












  • Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
    – laalto
    Nov 21 at 11:20










  • @Basti You have change your database version ?
    – Hardik Parmar
    Nov 21 at 16:48








1




1




Why not just delete from LogEntry. Then you don't need to recreate it
– juergen d
Nov 21 at 10:17




Why not just delete from LogEntry. Then you don't need to recreate it
– juergen d
Nov 21 at 10:17












@juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
– Basti
Nov 21 at 10:36




@juergend That would be a possible workaround, but i dont need the table once its empty. Im mostly interested in the reason why the drop statement executes but doesn't have any effect.
– Basti
Nov 21 at 10:36












beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
– Fantômas
Nov 21 at 10:53






beginTransaction() has to be called BEFORE executing your SQL commands. rawQuery() is only used to run queries, not commands. It's actually execSql(), not executeSql()
– Fantômas
Nov 21 at 10:53














Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
– laalto
Nov 21 at 11:20




Where exactly do you have the transaction? Note the blockquote in @MikeT's answer talking about nested transactions - SQLiteOpenHelper lifecycle callbacks are already run inside a transaction.
– laalto
Nov 21 at 11:20












@Basti You have change your database version ?
– Hardik Parmar
Nov 21 at 16:48




@Basti You have change your database version ?
– Hardik Parmar
Nov 21 at 16:48












1 Answer
1






active

oldest

votes


















1














I believe, assuimg #'s are .'s, the reason is that you have omitted the setTransactionSuccessful, without this endTransaction will rollback (undo everything done in the transaction).



As per :-




Transactions can be nested. When the outer transaction is ended all of
the work done in that transaction and all of the nested transactions
will be committed or rolled back. The changes will be rolled back if
any transaction is ended without being marked as clean (by calling
setTransactionSuccessful)
. Otherwise they will be committed.




beginTransaction






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    1 Answer
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    active

    oldest

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    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    1














    I believe, assuimg #'s are .'s, the reason is that you have omitted the setTransactionSuccessful, without this endTransaction will rollback (undo everything done in the transaction).



    As per :-




    Transactions can be nested. When the outer transaction is ended all of
    the work done in that transaction and all of the nested transactions
    will be committed or rolled back. The changes will be rolled back if
    any transaction is ended without being marked as clean (by calling
    setTransactionSuccessful)
    . Otherwise they will be committed.




    beginTransaction






    share|improve this answer


























      1














      I believe, assuimg #'s are .'s, the reason is that you have omitted the setTransactionSuccessful, without this endTransaction will rollback (undo everything done in the transaction).



      As per :-




      Transactions can be nested. When the outer transaction is ended all of
      the work done in that transaction and all of the nested transactions
      will be committed or rolled back. The changes will be rolled back if
      any transaction is ended without being marked as clean (by calling
      setTransactionSuccessful)
      . Otherwise they will be committed.




      beginTransaction






      share|improve this answer
























        1












        1








        1






        I believe, assuimg #'s are .'s, the reason is that you have omitted the setTransactionSuccessful, without this endTransaction will rollback (undo everything done in the transaction).



        As per :-




        Transactions can be nested. When the outer transaction is ended all of
        the work done in that transaction and all of the nested transactions
        will be committed or rolled back. The changes will be rolled back if
        any transaction is ended without being marked as clean (by calling
        setTransactionSuccessful)
        . Otherwise they will be committed.




        beginTransaction






        share|improve this answer












        I believe, assuimg #'s are .'s, the reason is that you have omitted the setTransactionSuccessful, without this endTransaction will rollback (undo everything done in the transaction).



        As per :-




        Transactions can be nested. When the outer transaction is ended all of
        the work done in that transaction and all of the nested transactions
        will be committed or rolled back. The changes will be rolled back if
        any transaction is ended without being marked as clean (by calling
        setTransactionSuccessful)
        . Otherwise they will be committed.




        beginTransaction







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 21 at 10:56









        MikeT

        14.8k102441




        14.8k102441






























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