Develop Reference

SQLite query compare content Values

How can I compare column content values? So if content values contain "ted" return all data in cursor.
public Cursor listNotes() {
String username = session.getUser();
String query = "SELECT * FROM Task WHERE " +help.Column_owner+ " = " +username ;
Cursor c = db.rawQuery(query, null);
return c;
}
Here is the error, I am trying to compare username to the content values in the column_create but its not working
no such column: ted (code 1): , while compiling: SELECT * FROM Notes WHERE column_owner = ted

username must be enclosed in apostrophes ('), because it is a string!
Correct your code like this:
String query = "SELECT * FROM Task WHERE " + help.Column_owner + " = '" +username + "'";
Or, better, use a bound parameter (in this case, Android takes care of the apostrophes for you and you're less prone to SQL injection - and, last but not least, you use less string concatenations):
String query = "SELECT * FROM Task WHERE " + help.Column_owner + " = ?";
Cursor c = db.rawQuery(query, new String[]{username});

Android Sqlite rawquery selection args[] with "WHERE x IN(y)" [duplicate]

I'm attempting to do the following SQL query within Android:
String names = "'name1', 'name2"; // in the code this is dynamically generated
String query = "SELECT * FROM table WHERE name IN (?)";
Cursor cursor = mDb.rawQuery(query, new String[]{names});
However, Android does not replace the question mark with the correct values. I could do the following, however, this does not protect against SQL injection:
String query = "SELECT * FROM table WHERE name IN (" + names + ")";
Cursor cursor = mDb.rawQuery(query, null);
How can I get around this issue and be able to use the IN clause?

A string of the form "?, ?, ..., ?" can be a dynamically created string and safely put into the original SQL query (because it is a restricted form that does not contain external data) and then the placeholders can be used as normal.
Consider a function String makePlaceholders(int len) which returns len question-marks separated with commas, then:
String[] names = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host parameters in SQLite is 999 - at least in a normal build, not sure about Android :)
Here is one implementation:
String makePlaceholders(int len) {
if (len < 1) {
// It will lead to an invalid query anyway ..
throw new RuntimeException("No placeholders");
} else {
StringBuilder sb = new StringBuilder(len * 2 - 1);
sb.append("?");
for (int i = 1; i < len; i++) {
sb.append(",?");
}
return sb.toString();
}
}

Short example, based on answer of user166390:
public Cursor selectRowsByCodes(String[] codes) {
try {
SQLiteDatabase db = getReadableDatabase();
SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
String[] sqlSelect = {COLUMN_NAME_ID, COLUMN_NAME_CODE, COLUMN_NAME_NAME, COLUMN_NAME_PURPOSE, COLUMN_NAME_STATUS};
String sqlTables = "Enumbers";
qb.setTables(sqlTables);
Cursor c = qb.query(db, sqlSelect, COLUMN_NAME_CODE+" IN (" +
TextUtils.join(",", Collections.nCopies(codes.length, "?")) +
")", codes,
null, null, null);
c.moveToFirst();
return c;
} catch (Exception e) {
Log.e(this.getClass().getCanonicalName(), e.getMessage() + e.getStackTrace().toString());
}
return null;
}

Sadly there's no way of doing that (obviously 'name1', 'name2' is not a single value and can therefore not be used in a prepared statement).
So you will have to lower your sights (e.g. by creating very specific, not reusable queries like WHERE name IN (?, ?, ?)) or not using stored procedures and try to prevent SQL injections with some other techniques...

As suggest in accepted answer but without using custom function to generate comma-separated '?'. Please check code below.
String[] names = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + TextUtils.join(",", Collections.nCopies(names.length, "?")) + ")";
Cursor cursor = mDb.rawQuery(query, names);

You can use TextUtils.join(",", parameters) to take advantage of sqlite binding parameters, where parameters is a list with "?" placeholders and the result string is something like "?,?,..,?".
Here is a little example:
Set<Integer> positionsSet = membersListCursorAdapter.getCurrentCheckedPosition();
List<String> ids = new ArrayList<>();
List<String> parameters = new ArrayList<>();
for (Integer position : positionsSet) {
ids.add(String.valueOf(membersListCursorAdapter.getItemId(position)));
parameters.add("?");
}
getActivity().getContentResolver().delete(
SharedUserTable.CONTENT_URI,
SharedUserTable._ID + " in (" + TextUtils.join(",", parameters) + ")",
ids.toArray(new String[ids.size()])
);

Actually you could use android's native way of querying instead of rawQuery:
public int updateContactsByServerIds(ArrayList<Integer> serverIds, final long groupId) {
final int serverIdsCount = serverIds.size()-1; // 0 for one and only id, -1 if empty list
final StringBuilder ids = new StringBuilder("");
if (serverIdsCount>0) // ambiguous "if" but -1 leads to endless cycle
for (int i = 0; i < serverIdsCount; i++)
ids.append(String.valueOf(serverIds.get(i))).append(",");
// add last (or one and only) id without comma
ids.append(String.valueOf(serverIds.get(serverIdsCount))); //-1 throws exception
// remove last comma
Log.i(this,"whereIdsList: "+ids);
final String whereClause = Tables.Contacts.USER_ID + " IN ("+ids+")";
final ContentValues args = new ContentValues();
args.put(Tables.Contacts.GROUP_ID, groupId);
int numberOfRowsAffected = 0;
SQLiteDatabase db = dbAdapter.getWritableDatabase());
try {
numberOfRowsAffected = db.update(Tables.Contacts.TABLE_NAME, args, whereClause, null);
} catch (Exception e) {
e.printStackTrace();
}
dbAdapter.closeWritableDB();
Log.d(TAG, "updateContactsByServerIds() numberOfRowsAffected: " + numberOfRowsAffected);
return numberOfRowsAffected;
}

This is not Valid
String subQuery = "SELECT _id FROM tnl_partofspeech where part_of_speech = 'noun'";
Cursor cursor = SQLDataBase.rawQuery(
"SELECT * FROM table_main where part_of_speech_id IN (" +
"?" +
")",
new String[]{subQuery}););
This is Valid
String subQuery = "SELECT _id FROM tbl_partofspeech where part_of_speech = 'noun'";
Cursor cursor = SQLDataBase.rawQuery(
"SELECT * FROM table_main where part_of_speech_id IN (" +
subQuery +
")",
null);
Using ContentResolver
String subQuery = "SELECT _id FROM tbl_partofspeech where part_of_speech = 'noun' ";
final String[] selectionArgs = new String[]{"1","2"};
final String selection = "_id IN ( ?,? )) AND part_of_speech_id IN (( " + subQuery + ") ";
SQLiteDatabase SQLDataBase = DataBaseManage.getReadableDatabase(this);
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables("tableName");
Cursor cursor = queryBuilder.query(SQLDataBase, null, selection, selectionArgs, null,
null, null);

In Kotlin you can use joinToString
val query = "SELECT * FROM table WHERE name IN (${names.joinToString(separator = ",") { "?" }})"
val cursor = mDb.rawQuery(query, names.toTypedArray())

I use the Stream API for this:
final String[] args = Stream.of("some","data","for","args").toArray(String[]::new);
final String placeholders = Stream.generate(() -> "?").limit(args.length).collect(Collectors.joining(","));
final String selection = String.format("SELECT * FROM table WHERE name IN(%s)", placeholders);
db.rawQuery(selection, args);

How to use SQL to search for a value?

I'm trying to learn how to use database in Android and so far I have learned how to fetch all rows of data in the table, but I'm not sure how I'm going to use a SQL query to search for a value that is equal to the string value I pass to the method below?
I wonder if someone could add some simple code how to query the database with SQL in my code? Preciate the help! Thanks!
Something like this: String query = "Select * from DB_TABLE where TABLE_IMAGE_PATH = filePath";
// Read from database
public String readContacts(String filePath){
String[] columns = new String[]{TABLE_ID, TABLE_IMAGE_PATH, TABLE_CONTACT_NAME, TABLE_CONTACT_NUMBER, TABLE_CONTACT_ADDRESS};
Cursor c = db.query(DB_TABLE, columns, null, null, null, null, null);
int id = c.getColumnIndex(TABLE_ID);
int imagePath = c.getColumnIndex(TABLE_IMAGE_PATH);
int name = c.getColumnIndex(TABLE_CONTACT_NAME);
int number = c.getColumnIndex(TABLE_CONTACT_NUMBER);
int address = c.getColumnIndex(TABLE_CONTACT_ADDRESS);
String result = "";
for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result = result + c.getString(id) + " " + c.getString(imagePath) + " " + c.getString(name) + " " + c.getString(number) + " " + c.getString(address);
}
return result;
}

You can search Query
its for exact string
String query = "Select * from DB_TABLE where TABLE_IMAGE_PATH like '"+filePath+"';
if value contains your string
String query = "Select * from DB_TABLE where TABLE_IMAGE_PATH like '%"+filePath+"%';
if value needs from last
String query = "Select * from DB_TABLE where TABLE_IMAGE_PATH like '%"+filePath+"';
if value needs from first
String query = "Select * from DB_TABLE where TABLE_IMAGE_PATH like '"+filePath+"%';
put these
SQLiteDatabase dbR = this.getReadableDatabase();
Cursor cur = dbR.rawQuery("query", null);
return cur
using this cursor you can get value.

you can do that easily by modifying your query code to:
String[] columns = new String[]{TABLE_ID, TABLE_IMAGE_PATH, TABLE_CONTACT_NAME, TABLE_CONTACT_NUMBER, TABLE_CONTACT_ADDRESS};
Cursor cursor = db.query(ANSWERS_TABLE,
columns,
columns[1] + " = ?", new String[]{filePath}, null, null, null);
Take a look here : SQLiteDataBase Query

how to retrieve a specific string data from sqlite database by using 2 string arguments?

this is my code used which i use for making method
String item = item1.getText().toString();
item = item.toLowerCase();
String date = getDate();
edited = new Datahelper(this);
edited.open();
String returnedprice = edited.getprice(item,date);
String returneddetail = edited.getdetail(item,date);
edited.close();
price.setText(returnedprice);
details.setText(returneddetail);
and this is my code of method that i am using for getting that string but here i dont know how to use the 2nd date string so that the string price that return is from a row that contains that item and that date.. please give me the code of how to do it..
public String getprice(String item ,String date) {
// TODO Auto-generated method stub
String[] columns = new String[]{KEY_ROWID,
KEY_CATEGORY,KEY_DATE,KEY_PRICE,KEY_DETAILS};
Cursor v =ourDatabase.query(DATABASE_TABLE, columns, KEY_CATEGORY + " ='" + item
+"'",null,null, null, null);
if(v!=null){
String price = v.getString(3);
return price;
}
return null;
}
public String getdetail(String item,String date) {
// TODO Auto-generated method stub
String[] columns = new String[]{KEY_ROWID,
KEY_CATEGORY,KEY_DATE,KEY_PRICE,KEY_DETAILS};
Cursor v =ourDatabase.query(DATABASE_TABLE, columns, KEY_CATEGORY + " ='" + item +
"'",null,null, null, null);
if(v!=null){
String detail = v.getString(4);
return detail;
}
return null;
}

So probably you want to use two arguments in select query so:
You can use two methods:
rawQuery()
query()
I will give you basic example for both cases.
First:
String query = "select * from Table where someColumn = ? and someDateColumn = ?";
Cursor c = db.rawQuery(query, new String[] {textValue, dateValue});
Explanation:
So i recommend to you use ? that is called placeholder.
Each placeholder in select statement will be replaced(in same order so first placeholder will be replaced by first value in array etc.) by values from selectionArgs - it's String array declared above.
Second:
rawQuery() method was easier to understand so i started with its. Query() method is more complex and has a little bit more arguments. So
columns: represents array of columns will be selected.
selection: is in other words where clause so if your selection is
KEY_COL + " = ?" it means "where " + KEY_COL + " = ?"
selectionArgs: each placeholder will be replaced with value from this
array.
groupBy: it's multi-row (grouping) function. more
about
having: this clause is always used with group by clause here is
explanation
orderBy: is clause used for sorting rows based on one or multiple
columns
Also method has more arguments but now you don't need to care about them. If you will, Google will be your friend.
So let's back to explanation and example:
String[] columns = {KEY_COL1, KEY_COL2};
String whereClause = KEY_CATEGORY " = ? and " + KEY_DATE + " = ?";
String[] whereArgs = {"data1", "data2"};
Cursor c = db.query("Table", columns, whereClause, whereArgs, null, null, null);
So whereClause contains two arguments with placeholder for each. So first placeholder will be replaced with "data1" and second with "data2".
When query is performed, query will look like:
SELECT col1, col2 FROM Table WHERE category = 'data1' AND date = 'data2'
Note: I recommend to you have look at Android SQLite Database and ContentProvider - Tutorial.
Also i recommend to you an usage of placeholders which provide safer and much more readable and clear solutions.

You should read any SQL tutorial to find out what a WHERE clause it and how to write it.
In Android, the selection parameter is the expression in the WHERE clause.
Your query could be written like this:
c = db.query(DATABASE_TABLE, columns,
KEY_CATEGORY + " = ? AND " + KEY_DATE + " = ?",
new String[] { item, date },
null, null, null);

SQLite Query in Android to count rows

I'm trying to create a simple Login form, where I compare the login id and password entered at the login screen with that stored in the database.
I'm using the following query:
final String DATABASE_COMPARE =
"select count(*) from users where uname=" + loginname + "and pwd=" + loginpass + ");" ;
The issue is, I don't know, how can I execute the above query and store the count returned.
Here's how the database table looks like ( I've manged to create the database successfully using the execSQl method)
private static final String
DATABASE_CREATE =
"create table users (_id integer autoincrement, "
+ "name text not null, uname primary key text not null, "
+ "pwd text not null);";//+"phoneno text not null);";
Can someone kindly guide me as to how I can achieve this? If possible please provide a sample snippet to do the above task.

DatabaseUtils.queryNumEntries (since api:11) is useful alternative that negates the need for raw SQL(yay!).
SQLiteDatabase db = getReadableDatabase();
DatabaseUtils.queryNumEntries(db, "users",
"uname=? AND pwd=?", new String[] {loginname,loginpass});

#scottyab the parametrized DatabaseUtils.queryNumEntries(db, table, whereparams) exists at API 11 +, the one without the whereparams exists since API 1. The answer would have to be creating a Cursor with a db.rawQuery:
Cursor mCount= db.rawQuery("select count(*) from users where uname='" + loginname + "' and pwd='" + loginpass +"'", null);
mCount.moveToFirst();
int count= mCount.getInt(0);
mCount.close();
I also like #Dre's answer, with the parameterized query.

Use an SQLiteStatement.
e.g.
SQLiteStatement s = mDb.compileStatement( "select count(*) from users where uname='" + loginname + "' and pwd='" + loginpass + "'; " );
long count = s.simpleQueryForLong();

See rawQuery(String, String[]) and the documentation for Cursor
Your DADABASE_COMPARE SQL statement is currently invalid, loginname and loginpass won't be escaped, there is no space between loginname and the and, and you end the statement with ); instead of ; -- If you were logging in as bob with the password of password, that statement would end up as
select count(*) from users where uname=boband pwd=password);
Also, you should probably use the selectionArgs feature, instead of concatenating loginname and loginpass.
To use selectionArgs you would do something like
final String SQL_STATEMENT = "SELECT COUNT(*) FROM users WHERE uname=? AND pwd=?";
private void someMethod() {
Cursor c = db.rawQuery(SQL_STATEMENT, new String[] { loginname, loginpass });
...
}

Assuming you already have a Database (db) connection established, I think the most elegant way is to stick to the Cursor class, and do something like:
String selection = "uname = ? AND pwd = ?";
String[] selectionArgs = {loginname, loginpass};
String tableName = "YourTable";
Cursor c = db.query(tableName, null, selection, selectionArgs, null, null, null);
int result = c.getCount();
c.close();
return result;

how to get count column
final String DATABASE_COMPARE = "select count(*) from users where uname="+loginname+ "and pwd="+loginpass;
int sometotal = (int) DatabaseUtils.longForQuery(db, DATABASE_COMPARE, null);
This is the most concise and precise alternative. No need to handle cursors and their closing.

If you are using ContentProvider then you can use:
Cursor cursor = getContentResolver().query(CONTENT_URI, new String[] {"count(*)"},
uname=" + loginname + " and pwd=" + loginpass, null, null);
cursor.moveToFirst();
int count = cursor.getInt(0);

If you want to get the count of records then you have to apply the group by on some field or apply the below query.
Like
db.rawQuery("select count(field) as count_record from tablename where field =" + condition, null);

Another way would be using:
myCursor.getCount();
on a Cursor like:
Cursor myCursor = db.query(table_Name, new String[] { row_Username },
row_Username + " =? AND " + row_Password + " =?",
new String[] { entered_Password, entered_Password },
null, null, null);
If you can think of getting away from the raw query.

int nombr = 0;
Cursor cursor = sqlDatabase.rawQuery("SELECT column FROM table WHERE column = Value", null);
nombr = cursor.getCount();