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Firebase Search-Nested object searching in Firebase Android

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0

I want to search by string value of the child "title" from all the "category" child:

database snapshot

I've add database rules like this:

database rules snapshot

I tried with this code:

public void getData(String search_key) 
 dbref.child("data").orderByChild("title").startAt(search_key).endAt(search_key + "uf8ff").addListenerForSingleValueEvent(new ValueEventListener() 
 @Override
 public void onDataChange(@NonNull DataSnapshot dataSnapshot) 
 String title = null;
 for (DataSnapshot data:dataSnapshot.getChildren()) 
 for (DataSnapshot dataCategory:data.getChildren()) 
 try 
 Object object = dataCategory.child(DBConstants.CHILD_TITLE).getValue();
 if (object != null) title = object.toString();
 catch (NullPointerException e) 
 //comments
 
 System.out.println(title);
 
 
 

 @Override
 public void onCancelled(@NonNull DatabaseError databaseError) 

 
 );

java android firebase firebase-realtime-database

share|improve this question

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

add a comment | 

0

I want to search by string value of the child "title" from all the "category" child:

database snapshot

I've add database rules like this:

database rules snapshot

I tried with this code:

public void getData(String search_key) 
 dbref.child("data").orderByChild("title").startAt(search_key).endAt(search_key + "uf8ff").addListenerForSingleValueEvent(new ValueEventListener() 
 @Override
 public void onDataChange(@NonNull DataSnapshot dataSnapshot) 
 String title = null;
 for (DataSnapshot data:dataSnapshot.getChildren()) 
 for (DataSnapshot dataCategory:data.getChildren()) 
 try 
 Object object = dataCategory.child(DBConstants.CHILD_TITLE).getValue();
 if (object != null) title = object.toString();
 catch (NullPointerException e) 
 //comments
 
 System.out.println(title);
 
 
 

 @Override
 public void onCancelled(@NonNull DatabaseError databaseError) 

 
 );

java android firebase firebase-realtime-database

share|improve this question

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

add a comment | 

I want to search by string value of the child "title" from all the "category" child:

database snapshot

I've add database rules like this:

database rules snapshot

I tried with this code:

public void getData(String search_key) 
 dbref.child("data").orderByChild("title").startAt(search_key).endAt(search_key + "uf8ff").addListenerForSingleValueEvent(new ValueEventListener() 
 @Override
 public void onDataChange(@NonNull DataSnapshot dataSnapshot) 
 String title = null;
 for (DataSnapshot data:dataSnapshot.getChildren()) 
 for (DataSnapshot dataCategory:data.getChildren()) 
 try 
 Object object = dataCategory.child(DBConstants.CHILD_TITLE).getValue();
 if (object != null) title = object.toString();
 catch (NullPointerException e) 
 //comments
 
 System.out.println(title);
 
 
 

 @Override
 public void onCancelled(@NonNull DatabaseError databaseError) 

 
 );

java android firebase firebase-realtime-database

share|improve this question

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

public void getData(String search_key) 
 dbref.child("data").orderByChild("title").startAt(search_key).endAt(search_key + "uf8ff").addListenerForSingleValueEvent(new ValueEventListener() 
 @Override
 public void onDataChange(@NonNull DataSnapshot dataSnapshot) 
 String title = null;
 for (DataSnapshot data:dataSnapshot.getChildren()) 
 for (DataSnapshot dataCategory:data.getChildren()) 
 try 
 Object object = dataCategory.child(DBConstants.CHILD_TITLE).getValue();
 if (object != null) title = object.toString();
 catch (NullPointerException e) 
 //comments
 
 System.out.println(title);
 
 
 

 @Override
 public void onCancelled(@NonNull DatabaseError databaseError) 

 
 );

java android firebase firebase-realtime-database

java android firebase firebase-realtime-database

share|improve this question

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

share|improve this question

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

edited Mar 22 at 9:39

Alex Mamo

47.1k82965

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

asked Mar 21 at 22:48

Nasimul HaqueNasimul Haque

32

1 Answer
1

active

oldest

votes

0

There is no way you can achieve this using your database structure since between your data node and the objects that contain the title property there is one more child, the Category.

You can use the following query:

dbref.child("data").child("Category1")
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

And loop only once, not twice as you do in your code right now but you'll be able to get only the titles that exist within the Category1 node. If you want to get all titles you should restructure your database by ading the category as a property of your objects and then simply use:

dbref.child("data") //No Category1 child
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

In this way you'll a have level less and this query will work perfectly fine.

share|improve this answer

edited Mar 24 at 8:37

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thank you. I've got the idea.
  
  – Nasimul Haque
  Mar 22 at 12:12
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're welcome, cheers!
  
  – Alex Mamo
  Mar 22 at 12:13
  

  
  
  
  

add a comment | 

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0

There is no way you can achieve this using your database structure since between your data node and the objects that contain the title property there is one more child, the Category.

You can use the following query:

dbref.child("data").child("Category1")
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

And loop only once, not twice as you do in your code right now but you'll be able to get only the titles that exist within the Category1 node. If you want to get all titles you should restructure your database by ading the category as a property of your objects and then simply use:

dbref.child("data") //No Category1 child
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

In this way you'll a have level less and this query will work perfectly fine.

share|improve this answer

edited Mar 24 at 8:37

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thank you. I've got the idea.
  
  – Nasimul Haque
  Mar 22 at 12:12
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're welcome, cheers!
  
  – Alex Mamo
  Mar 22 at 12:13
  

  
  
  
  

add a comment | 

0

There is no way you can achieve this using your database structure since between your data node and the objects that contain the title property there is one more child, the Category.

You can use the following query:

dbref.child("data").child("Category1")
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

And loop only once, not twice as you do in your code right now but you'll be able to get only the titles that exist within the Category1 node. If you want to get all titles you should restructure your database by ading the category as a property of your objects and then simply use:

dbref.child("data") //No Category1 child
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

In this way you'll a have level less and this query will work perfectly fine.

share|improve this answer

edited Mar 24 at 8:37

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thank you. I've got the idea.
  
  – Nasimul Haque
  Mar 22 at 12:12
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're welcome, cheers!
  
  – Alex Mamo
  Mar 22 at 12:13
  

  
  
  
  

add a comment | 

There is no way you can achieve this using your database structure since between your data node and the objects that contain the title property there is one more child, the Category.

You can use the following query:

dbref.child("data").child("Category1")
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

And loop only once, not twice as you do in your code right now but you'll be able to get only the titles that exist within the Category1 node. If you want to get all titles you should restructure your database by ading the category as a property of your objects and then simply use:

dbref.child("data") //No Category1 child
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

In this way you'll a have level less and this query will work perfectly fine.

share|improve this answer

edited Mar 24 at 8:37

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

dbref.child("data").child("Category1")
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

dbref.child("data") //No Category1 child
 .orderByChild("title")
 .startAt(search_key)
 .endAt(search_key + "uf8ff")
 .addListenerForSingleValueEvent(/* ... */);

share|improve this answer

edited Mar 24 at 8:37

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965

answered Mar 22 at 9:38

Alex MamoAlex Mamo

47.1k82965