I am trying to use this query upon my Android database, but it does not return any data. Am I missing something?
SQLiteDatabase db = mDbHelper.getReadableDatabase();
String select = "Select _id, title, title_raw from search Where(title_raw like " + "'%Smith%'" +
")";
Cursor cursor = db.query(TABLE_NAME, FROM,
select, null, null, null, null);
startManagingCursor(cursor);
return cursor;
answer
This will return you the required cursor
Cursor cursor = db.query(TABLE_NAME, new String[] {"_id", "title", "title_raw"},
"title_raw like " + "'%Smith%'", null, null, null, null);
answer
Alternatively, db.rawQuery(sql, selectionArgs) exists.
Cursor c = db.rawQuery(select, null);
answer
This will also work if the pattern you want to match is a variable.
dbh = new DbHelper(this);
SQLiteDatabase db = dbh.getWritableDatabase();
Cursor c = db.query("TableName", new String[]{"ColumnName"}
, "ColumnName LIKE ?" ,new String[]{_data+"%"}, null, null, null);
while(c.moveToNext())
{
// your calculation goes here
}
answer
I came here for a reminder of how to set up the query but the existing examples were hard to follow. Here is an example with more explanation.
SQLiteDatabase db = helper.getReadableDatabase();
String table = "table2";
String[] columns = {"column1", "column3"};
String selection = "column3 =?";
String[] selectionArgs = {"apple"};
String groupBy = null;
String having = null;
String orderBy = "column3 DESC";
String limit = "10";
Cursor cursor = db.query(table, columns, selection, selectionArgs, groupBy, having, orderBy, limit);
Parameters
table
: the name of the table you want to querycolumns
: the column names that you want returned. Don't return data that you don't need.selection
: the row data that you want returned from the columns (This is the WHERE clause.)selectionArgs
: This is substituted for the?
in theselection
String above.groupBy
andhaving
: This groups duplicate data in a column with data having certain conditions. Any unneeded parameters can be set to null.orderBy
: sort the datalimit
: limit the number of results to return
answer
Try this, this works for my code name is a String:
cursor = rdb.query(true, TABLE_PROFILE, new String[] { ID,
REMOTEID, FIRSTNAME, LASTNAME, EMAIL, GENDER, AGE, DOB,
ROLEID, NATIONALID, URL, IMAGEURL },
LASTNAME + " like ?", new String[]{ name+"%" }, null, null, null, null);
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