Can I create index on a column in the create table command in sqlite?I tried this command below in sqlite3 in Android shell. It seems to work.But, in sqlite's query language specification, specifying a column to be indexed is not supported.
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I have a TEXT column and I want to match all rows where the value has a certain prefix. For example, WHERE mycol LIKE 'myprefix%' However, I noticed in some optimization guidelines that this will not use the index and instead you should do this:WHERE mycol >= 'myprefix' AND mycol < 'myprefiy'Instead of simple A-Z chars, I have a whole variety of UTF-8 chars (think chinese characters).My question is, how to work out the next char in UTF-8? Is it enough to add one to the codepoint,
View 3 Replies View RelatedI am trying to utilize what has allready been written for this, in my own database
I will actually post my code so someone may be able to pick out what is wrong
This is the error i get: 06-21 19:57:35.511: ERROR/AndroidRuntime(796): Caused by:
code:................
This is the method its faulting on in Class:
code:..............................
I have a database that I download external and save on my sdcard. But this database is also used for an iPhone app and has a column id and not _id (sqlite uses _id). How can i rename this column to _id?
View 4 Replies View RelatedSo I have an app on the market, and with an update I want to add some columns to the database. No problems so far. But I want to detect if the database in use is missing these columns, and add them if this is the case. I need this to be done dynamically and not just after the update to the new version, because the application is supposed to still be able to import older databases. Normally I would be able to use the PRAGMA query, but Im not sure how to do this with Android. I cant use execSQL since it is a query, and I cant figure out how to use PRAGMA with the query()-function.
Ofcourse I could just catch exceptions and then add the column, or always add the columns to each table before I start to work with it, but that is not a neat solution.
I am trying to update a datetime column in an android sqlite db to use international date format (yyyy-mm-dd) instead of the current format (mm/dd/yyyy). I want to use the sqlite date() function to reformat the current value of the column. I thought it would be as simple as the following: update tblename set thedate = date(thedate)
But the above does not work.
How would i write the sql statement to accomplish this?
I'm working on an Android App where the user has different options for sorting the displayed data that comes from the database. Currently my orderBy string that I pass to Androids query() method looks like this:
"LOWER("+columnName+") ASC"
The problem with this is that if the data type in the column specified by columnName is integer, calling LOWER() on it will cause it to be sorted alphabetically, i.e. based only on the leftmost digit, which of course doesn't make any sense for numeric data. Hence I only want to apply LOWER() if the data type of the column is not integer. What I have in mind is a statement like this:
"CASE WHEN [data type of columnName is integer] THEN "+columnName+" ASC ELSE LOWER("+columName+") ASC END"
The part in the brackets is what I don't know how to do. Does SQLite provide a function to determine a column's data type?
I'm attempting to create a method that will allow me to retrieve a value from the last row of a database, and then insert it into an EditText field. (This is a value that the user will not change all that often, so it would be helpful if when they do set it, it stays set when they come back to it).
My method, based on a similar method I have for getting the total of a specific column, is as such. code...
If I run the program without this statement, it works fine and the value saves to the db. As soon as I try to run it with this, I get a force close. Any suggestions?
I am developing an application in android allowing the user to maintain his weight by providing him diet suggestions. I have done with that part and now, I need to display user weight tracking details using bar graph. I am able to fetch the Weight and Login date column data from the sqlite database to List<String>. I don't understand the way to put these values into a Bar Graph with Date Column data as X-axis and Weight column data as Y-axis.
View 1 Replies View RelatedSee title for explanation.
Here is the method I'm using:
CODE:.........
And here is the call to the method:
CODE:...........
Why it would be throwing the "No Column Found with name=Test", although my DB explorer shows there is indeed a column named name and a value in a row named Test?
I have a relative layout which looks like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:id="@+id/nameText"
android:layout_width="wrap_content"......................
How to create a table without primary key but it has one autoincrement column.
View 2 Replies View RelatedI created a sql lite database with the following columns:
static final String dbName="demoDB";
static final String tableName="Employees";
static final String colID="EmployeeID";
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL("CREATE TABLE "+tableName+" ("+colID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+
colName+" TEXT, "+colAge+" Integer);");
I want to select all the records in the database like this and display them in a gridview:SQLiteDatabase db=this.getWritableDatabase();Cursor cur= db.rawQuery("Select "+colName+", "+colAge+" from "+tableName, new String [] {});String [] from=new String []{DatabaseHelper.colName,DatabaseHelper.colAge};
int [] to=new int [] {R.id.colName,R.id.colAge};
SimpleCursorAdapter sca=new SimpleCursorAdapter(this,R.layout.gridrow,c,from,to);
GridView grid=(GridView)findViewById(R.id.grid);
grid.setAdapter(sca);but i receive the following exception:java.lang.IllegalArgumentException: column '_id' does not exist.the db table does not have a column with name '_id'so what is wrong with this code
This has got me all confused! I'm trying to return the max value from a column in my database but the return value is always the name of the column.
The query I use:
private static final String SELECTMAX = "SELECT MAX(?) FROM " + TABLE_NAME ;
The (test) function to return the max value:
CODE:............
The column i'm querying is an INTEGER type but the result 's' is always the column name and not the desired value.
We are building an Android App that will use user's current location (lat, long) and show top 50 venues around the current location, sorted by distance.We have these venues stored in an SQLite DB. We plan to ship with the sqlite DB with the app.In order to fetch only the relevant top 50 closest venues, we want to define a db function DIST (to calculate distance between two points) and use it in our query.How can I define a custom SQLite function for Android Apps? What will be the Java API call to do this?We have successfully implemented this approach in our iPhone App - using Objective C.
View 1 Replies View RelatedI am trying to use
SQLiteDatabase.openDatabase( "/data/data/edwin11.myapp/databases/myapp.db", null, (SQLiteDatabase.CREATE_IF_NECESSARY | SQLiteDatabase.NO_LOCALIZED_COLLATORS));
To create/open a database instead of making use of the SQLiteOpenHelper (because I want to pass in the flag SQLiteDatabase.NO_LOCALIZED_COLLATORS. However, I am getting this exception for that line of code:
04-18 09:50:03.585: ERROR/Database(3471): sqlite3_open_v2("/data/data/edwin11.myapp/databases/myapp.db", &handle, 6, NULL) failed
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): java.lang.RuntimeException: An error occured while executing doInBackground()
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at android.os.AsyncTask$3.done(AsyncTask.java:200)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:234)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:258)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.util.concurrent.FutureTask.run(FutureTask.java:122)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:648)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:673)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at java.lang.Thread.run(Thread.java:1060)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): Caused by: android.database.sqlite.SQLiteException: unable to open database file
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1584)
04-18 09:50:03.665: ERROR/AndroidRuntime(3471): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:638)...
Doing some testing just before that line of code (using File.isExists) shows that the file /data/data/edwin11.myapp/databases/myapp.db does not exist. Would that be the cause of the error? (Or am I just using SQLiteDatabase.openDatabase the wrong way?) Would it help if I create the file beforehand? (Shouldn't that be taken care of by the SQLiteDatabase.CREATE_IF_NECESSARY flag that I passed in?) If creating the file manually is the way to go, is it just an empty file, or do I have to write something to it?
This is my code used to create table code...
View 1 Replies View RelatedI wrote two apps and submitted them to the marketplace last night (been roughly 12 hours now). One was a LITE version of my app and the next was a Standard version. Neither shows up in a search on the Marketplace even though the LITE version of my app has been installed 25 times already.Is there a lengthy approval process that goes on before an app is approved?
View 19 Replies View RelatedHow can I create database from txt or xml file that already have table structure in it?
View 1 Replies View RelatedI want to create a sqlite database by importing data from some data files, like csv etc., and then put this database into one of my android application and then deploy into the Android device.
By now the samples and tutorial what I found are all taliking about creating the sqlite database at runtime when running the android application on the device. Is there anyway I can create it offline and then attach it to my application later?
Any tools and docs for this?
I have certain needs that I am having trouble making an app for. I was hoping to be able to create a sqlite database that I can manually input data from my computer and search the data on my droid. I wanted to set up tags or full data search within each sqlite database object so and pull up a listing of best matches for the given search term.
The use for it is that I work on an Air Force Base and my job is very broad. I wanted to custom build an app that I could list all of the information pertaining to my job and be able to search it as I work to find solutions to problems way quicker than we are doing it now.
Is there any such app. I've been trying to create my own and it looks like it would be a mix between notepad and searchable dictionary but not quite.
the error in my logcat is such Logcat
08-29 08:20:57.961: ERROR/AndroidRuntime(1766): java.lang.RuntimeException: Unable to start activity ComponentInfo{one.two/one.two.Booking}: java.lang.IllegalArgumentException: column '_id' does not exist
08-29 08:20:57.961: ERROR/AndroidRuntime(1766): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2268)
08-29 08:20:57.961: ERROR/AndroidRuntime(1766): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2284).................
I had number of rows in my view now I want to add 2 columns for each row how to do this at runtime, I had tried but not succeed.
View 5 Replies View RelatedI'd like to get the value of Count column from cursor.
CODE:...............
I tried to get this count column value from cursor like below
Cursor cR = mDbHelper.getRCount(cplace);if (cR.getCount() > 0){long lCount = cR.getLong(0);}cR.close();}
I got the debug error. How to get it?
Could I use nested cursors?
I want to design a table whose first column items remain fixed when user scrolls horizontally, but should scroll when the user scrolls vertically. Similarly the first row items remain fixed when user scrolls vertically, but should scroll when the user scrolls horizontally. Can this be achieved using a TableLayout? Or is there any other combination of widgets that I could use?
View 2 Replies View RelatedOne of my android apps performs the following specific SQLite query:
CODE:................
Now that works on some Android phones, but on a few of them it crashes with the following error:
CODE:..................
For some reason, "-1" is interpreted as a column rather than a number... that doesn't make much sense and when I read the SQLite query language I see no need to escape this number in parentheses. Could it be an issue of a different version of SQLite? Would adding parentheses this help any? Instead, I'll probably rewrite it using >= 0 but still I'd like to understand what's going on.
I'm having trouble with something that works in the Notepad example.
Here's the code from the NotepadCodeLab/Notepadv1Solution:
CODE:.................
This code seems to work fine. But just to be clear, I ran the adb utility and run sqlite3 I inspected the schema as follows:
CODE:...............
All seems good to me.
Now on to My App, which as far as I can see is basically the same with a few minor changes. I've simplified and simplified my code, but the problem persists.
CODE:..............
When I run my app, I get a RuntimeException and the following prints in LogCat from my Log.e() statement:
LogCat Message: java.lang.IllegalArgumentException: column '_id' does not exist
So, back to sqlite3 to see what's different about my schema:
CODE:.................
I don't see how I'm missing the '_id'.
Can anyone point out what I've done wrong?
One thing that's different between my app and the Notepad example is that I started by creating my application from scratch using the Eclipse wizard while the sample app comes already put together. Is
there some sort of environmental change I need to make for a new app to use a sqlite database?
I'm not big into UI programming so this may be an easy thing I overlooked. I am trying have a screen that shows 8 TextView in a 2 column x 4 row table. And, of course, I want the TextViews, that might have different lengths, to be centered. I tried this in a table layout, for obvious reasons but I feel like this is not the way to do it because it doesn't have much control where I put everything once it is in a row. Should I be using a different combinations of layouts or is there something I overlooked.
View 2 Replies View RelatedIn my activity i am using table layout.I have 5 rows and 5 colums. To merge (or) span a columns in a row we use android:layout_span='2' I want to merge (or) span 2 rows in one column.
View 2 Replies View RelatedI am trying to use a list adapter. While querying, i need to have a column called "_id" which helps to scroll through the database. I have an other primary key in this table. Can I use a custom column name, or am i bound to the "_id" column.
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