Taking that into account, the behaviour of "changes" makes perfect sense (though the feature admittedly has an unfortunate name). Granted, it would, on average, normally have to compare far fewer columns, but the fact remains that, computationally speaking, that comparison could, for arbitrarily large fields in arbitrary numbers of rows, be expensive and would necessarily apply to every update because sqlite cannot predict whether the client would eventually ask for the number of modified rows. Such an update would, in order for "changes" to know whether anything was actually modified, compare up to 25 columns (a.y) which are irrelevant for the WHERE clause (i.e. Of course it has to read the rows, but my point is that it in order to know whether a row was actually modified (as oppose to "affected"), it would have to compare N fields unrelated to the WHERE clause: update t set a=1, b=2. SQLite has to read and parse the entire row anyway otherwise it would not be able to run triggers or re-write the row (update it). If the SELECT returns any rows, the UPDATE either succeeded or was not needed, but there definitely is a Row with that id and value now. SELECT 1 FROM table WHERE id=911 AND column_name=value Which is the only good way to know if id 911 exists in the table or not.Īnother way to check AFTER the fact if an update succeeded (if needed), is to formulate this: UPDATE table SET column_name=value WHERE id=911 In your ListViews OnItemClickListener, the onItemClick event takes the AdapterView as the first argument and the index of the selected item as the second. i think the problem is here: anId Integer.valueOf(( (AnSco) spnAnsco.getSelectedItem ). load from spinner sqlite with text and value. I used the code in the below link and get some exceptions. You really cannot get away from issuing: SELECT 1 FROM table WHERE id=911 The better route to go will be to fetch the id of the record from the object represented by ListView item and then use that to get the correct record in the database. The Id that i want to retrieve shall be the same that is in the sqlite database, not the id of the item row of the spinner. If that returns any row, then it means your update statement WILL modify the DB. If you want to know if it WILL modify a record, or if there was definitely a record to modify, you have to issue two statements, the first might be: SELECT 1 FROM table WHERE id=911 AND column_namevalue If you simply want to know if a record was modified or not, the page posted by others is perfect. : near 'bookpath': syntax error:, while compiling: SELECT lastchapter FROM Bookdetails INTOnothingWHERE bookpath i just want to take the result of the above query so that the string stored in lastchapter is available in tempaddress please help. In this case the result was 2, because this was the second record I’ve inserted into this table.Is there any method to check the update statement is really modify a record ?ĭo you mean if it "has modified" a record, or if it "will modify" a record? Now, just use the SQLite last_insert_rowid() function to get the value of the SQLite autoincrement field that was just generated: sqlite> select last_insert_rowid() Next, insert a record into this table, passing a null value into the SQLite autoincrement field: sqlite> INSERT INTO salespeople VALUES (null, 'Fred', 'Flinstone', 10.0) This only, for example, you can store any data as per requirement. We’ll store the user’s first and last name, you can store any number of data that you want to do. User data store in the SQLite database and display in ListView. (Note that this field is referred to as an autoincrement field, serial field, or identity column in other databases I have worked with.) So, friends, we’ll learn simple CRUD operations using the SQLite database. Here’s a short, complete example of how this works.įirst, let’s assume we have a SQLite database table defined like this: CREATE TABLE salespeople (Īs you can see, the id field is the PRIMARY KEY field for this SQLite table. How to get the SQLite autoincrement (primary key) value after an insert You can get the integer value of the primary key field from the last insert into an autoincrement field using a SQLite function named last_insert_rowid(), as shown in the example below. SQLite autoincrement FAQ: How do I get the autoincrement value from my last SQLite INSERT command?
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