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OrientDB – Delete Record



Delete Record command is used to delete one or more records completely from the database.

The following statement is the basic syntax of the Delete command.

DELETE FROM <Class>|cluster:<cluster>|index:<index> 
   [LOCK <default|record>] 
   [RETURN <returning>] 
   [WHERE <Condition>*] 
   [LIMIT <MaxRecords>] 
   [TIMEOUT <timeout>]

Following are the details about the options in the above syntax.

LOCK − Specifies how to lock the records between load and update. We have two options to specify Default and Record.

RETURN − Specifies an expression to return instead of the number of records.

LIMIT − Defines the maximum number of records to update.

TIMEOUT − Defines the time you want to allow the update run before it times out.

Note − Don’t use DELETE to remove Vertices or Edges because it effects the integrity of the graph.

Example

Let us consider the Customer table.

Sr.No. Name Age
1 Satish 25
2 Krishna 26
3 Kiran 29
4 Javeed 21

Try the following query to delete the record having id = 4.

orientdb {db = demo}> DELETE FROM Customer WHERE id = 4

If the above query is executed successfully, you will get the following output.

Delete 1 record(s) in 0.008000 sec(s).

To check the record of Customer table you can use the following query.

Orientdb {db = demo}> SELECT FROM Customer

If the above query is executed successfully, you will get the following output.

----+-----+--------+----+-------+---- 
#   |@RID |@CLASS  |id  |name   |age  
----+-----+--------+----+-------+---- 
0   |#11:0|Customer|1   |satish |25   
1   |#11:1|Customer|2   |krishna|26   
2   |#11:2|Customer|3   |kiran  |29 
----+-----+--------+----+-------+---- 

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