I have a problem with SQlite. Whenever I execute Queries it goes fine but when I exit by .exit command and open again and execute Select * form emp statement, it renders no table even though I use begin transaction and commit .
Any help please. I'm new to SQLite.
Thanks
Bamadeva
I got the solution:-
Wherever our database is created, in my case it is :-
C:\Sites\databases>
Since my database is contactlist_development, I should have entered it with the following commands:-
C:\Sites\databases>sqlite3 contactlist_development
This takes me to :-
sqlite>.schema
Then i am able to view the table details which i just created:)
Related
I'm using sqlte3.8.8, trying to create a trigger to clean old data. Here is the SQL that I put in:
CREATE TRIGGER "main"."NewTrigger" AFTER INSERT ON "historydata"
BEGIN
delete from historydata where id in (select id from historydata order by id limit 100000);
vacuum;
END;
But I got Syntax error on "vacuum;".However, it works fine in sqlite command line.
Is it the case that "vacuum" cannot be used in a trigger?
The documentation shows that only UPDATE/INSERT/DELETE/SELECT statements are allowed in a trigger body.
I am creating this oracle 11g statement inside a java String and then executing it in sql developer. I tried running it on the database and got a warning when the trigger
is created. But, when run from the code, I get the error mentioned in my title.
Please tell me where is the mistake and how i can fix it ?
CREATE OR REPLACE TRIGGER myschema.my_sequence_id BEFORE INSERT ON myschema.mytable
FOR EACH ROW BEGIN SELECT my_sequence_id.nextval INTO :new.mycolumn FROM DUAL; end; /
Thanks in advance !
You can't have a trigger named my_sequence_id if you already have a sequence my_sequence_id. They share the same namespace. Your trigger would need to be named something other than the name of the sequence (or any other object in the schema).
I have created a database "MyDB.sqlite" using the command line sqlite3 MyDB.sqlite in a specific folder(my desktop) and then created a table "tbl11" using create table syntax. I am able to insert record and can check the inserted records.
But when I exit command (terminal in Mac) line and re enter I can't see my database and tables in that folder. I guess this database and table are temporary by default. I even check the .databases command to see the database, but I can only see two database main!
please help!
Be sure to finish off with COMMIT; :-)
For practice, work through the short working example at http://souptonuts.sourceforge.net/readme_sqlite_tutorial.html
Good luck.
I am running a SQLite database in memory and I am attempting to drop a table with the following command.
DROP TABLE 'testing' ;
But when I execute the SQL statement, I get this error
SQL logic error or missing database
Before I run the "Drop Table" query I check to make sure that the table exists in the database with this query. So I am pretty sure that the table exists and I have a connection to the database.
SELECT count(*) FROM sqlite_master WHERE type='table' and name='testing';
This database is loaded in to memory from a file database and after I attempt to drop this table the database is saved from memory to the file system. I can then use a third party SQLite utility to view the SQLite file and check to see if the "testing" exists, it does. Using the same 3rd party SQLite utility I am able to run the "Drop TABLE" SQL statement with out error.
I am able to create/update tables without any problems.
My questions:
Is there a difference between a memory database and a file database in SQLite when dropping a table?
Is there a way to disable the ability to drop a table in SQLite that I may have accentually turned on somehow?
Edit: It appears to have something to do with a locked table. Still investigating.
You should not have quotes in your DROP TABLE command. Use this instead:
DROP TABLE testing
I had the same problem when using Sqlite with the xerial jbdc driver in the version 3.7.2. and JRE7
I first listed all the tables with the select command as follows:
SELECT name FROM sqlite_master WHERE type='table'
And then tried to delete a table like this:
DROP TABLE IF EXISTS TableName
I was working on a database stored on the file system and so it seems not to effect the outcome.
I used the IF EXISTS command to avoid listing all the table from the master table first, but I needed the complete table list anyway.
For me the solution was simply to change the order of the SELECT and DROP.
I want a debug function to do this, but I'm unaware of whether one already exists. Going through and using 'drop table' for each of my tables will be a pain.
Help appreciated.
Since the database is just one file, you can indeed just erase it. If you want something more automatic, you can use the following to do it all programmatically:
Recover your schema:
SELECT group_concat(sql,';') FROM sqlite_master;
Disconnect from the database
Delete the database file
Create your schema again with what was returned from the above query
If you used any particular options for your original database (page_size, etc), they will have to be declared manually as well.
to "drop database" for sqlite, simply delete the database file (and recreate if needed)