How does one check if a table exists in an Android SQLite database?
Try this one:
public boolean isTableExists(String tableName, boolean openDb) {
if(openDb) {
if(mDatabase == null || !mDatabase.isOpen()) {
mDatabase = getReadableDatabase();
}
if(!mDatabase.isReadOnly()) {
mDatabase.close();
mDatabase = getReadableDatabase();
}
}
String query = "select DISTINCT tbl_name from sqlite_master where tbl_name = '"+tableName+"'";
try (Cursor cursor = mDatabase.rawQuery(query, null)) {
if(cursor!=null) {
if(cursor.getCount()>0) {
return true;
}
}
return false;
}
}
This is what I did:
/* open database, if doesn't exist, create it */
SQLiteDatabase mDatabase = openOrCreateDatabase("exampleDb.db", SQLiteDatabase.CREATE_IF_NECESSARY,null);
Cursor c = null;
boolean tableExists = false;
/* get cursor on it */
try
{
c = mDatabase.query("tbl_example", null,
null, null, null, null, null);
tableExists = true;
}
catch (Exception e) {
/* fail */
Log.d(TAG, tblNameIn+" doesn't exist :(((");
}
return tableExists;
Although there are already a lot of good answers to this question, I came up with another solution that I think is more simple. Surround your query with a try block and the following catch:
catch (SQLiteException e){
if (e.getMessage().contains("no such table")){
Log.e(TAG, "Creating table " + TABLE_NAME + "because it doesn't exist!" );
// create table
// re-run query, etc.
}
}
It worked for me!
I know nothing about the Android SQLite API, but if you're able to talk to it in SQL directly, you can do this:
create table if not exists mytable (col1 type, col2 type);
Which will ensure that the table is always created and not throw any errors if it already existed.