- Which cursor is faster in Oracle?
- How Bulk collect improves performance?
- What is bulk binding in Oracle?
- What is bulk update?
- What is context switching in Oracle?
- What is ref cursor in Oracle?
- Does bulk collect overwrite?
- What is PL SQL collection?
- Why do we use save exceptions clause during bulk binding?
- How do you handle exceptions in bulk collect?
- What is bulk collect in Oracle?
- What is difference between bulk collect and bulk bind in Oracle?
- When should I use bulk collect?
- Can we commit inside a trigger?
- What is Oracle collection?
- What is Pragma Autonomous_transaction?
- Can we write commit in function or trigger or procedure?
- Why bulk collect is faster in Oracle?
- What is the use of limit clause in bulk collect in Oracle?
- How do you debug in PL SQL?
Which cursor is faster in Oracle?
The output from the procedure clearly demonstrates that implicit cursors are faster than explicit cursors.
The interesting thing is that the implicit cursor is not only faster, but it is actually doing more work, since it includes a NO_DATA_FOUND and a TOO_MANY_ROWS exception check..
How Bulk collect improves performance?
When you use BULK COLLECT, you retrieve more than row with each fetch, reducing context switching between the SQL and PL/SQL engines, and thereby improving performance.
What is bulk binding in Oracle?
Bulk Binds are a PL/SQL technique where, instead of multiple individual SELECT, INSERT, UPDATE or DELETE statements are executed to retrieve from, or store data in, at table, all of the operations are carried out at once, in bulk.
What is bulk update?
Updating data in Vector tables can be done as either a batch or bulk operation. Batch operations go to the PDTs (memory) by default. Bulk operations are written to the table files on disk by default. … UPDATE is a batch operation that quickly modifies a small number of records.
What is context switching in Oracle?
When we consider “CONTEXT SWITCHING” in relation to Oracle Database, we specifically refer to the exchange of processing control between the SQL and PL/SQL engines (without necessarily understanding what occurs in such a process). … This switch between two environments is known as a context switch.
What is ref cursor in Oracle?
Introduction to REF CURSORs Using REF CURSOR s is one of the most powerful, flexible, and scalable ways to return query results from an Oracle Database to a client application. A REF CURSOR is a PL/SQL data type whose value is the memory address of a query work area on the database.
Does bulk collect overwrite?
Is there any way that after the second bulk collect, data does not get override of the first bulk collect.
What is PL SQL collection?
A collection is an ordered group of elements having the same data type. Each element is identified by a unique subscript that represents its position in the collection. PL/SQL provides three collection types − Index-by tables or Associative array.
Why do we use save exceptions clause during bulk binding?
Description Add the SAVE EXCEPTIONS clause to your FORALL statement when you want the PL/SQL runtime engine to execute all DML statements generated by the FORALL, even if one or more than fail with an error. If you use INDICES OF, you will need to take some care to find your way back to the offending statement.
How do you handle exceptions in bulk collect?
Key components of bulk DML with exception handling:A collection variable to hold the data.The FORALL construct which iterates through values in the collection variable.The SAVE EXCEPTIONS clause which tracks the exceptions being raised during bulk DML.More items…•
What is bulk collect in Oracle?
A bulk collect is a method of fetching data where the PL/SQL engine tells the SQL engine to collect many rows at once and place them in a collection. The SQL engine retrieves all the rows and loads them into the collection and switches back to the PL/SQL engine.
What is difference between bulk collect and bulk bind in Oracle?
Bulk collect: is a CLAUSE. is used to fetch the records from the cursor. Forall: is a STATEMENT. is used to do dml operation of fetched records. The body of the FORALL statement is a single DML statement — an INSERT, UPDATE, or DELETE.
When should I use bulk collect?
When you are certain that the returning result of your SELECT statement is small then you should use Bulk Collect clause with Select-Into statement. Otherwise your bulk collect clause will make your Select-Into statement a memory hogging monster. Consequently it will slowdown the performance of your database.
Can we commit inside a trigger?
Trigger should not commit and cannot commit. Committing in a trigger usually raises an exception unless it happens into autonomous transaction. When you open connection, Oracle creates session for it.
What is Oracle collection?
A Collection is an ordered group of elements of particular data types. … Collections are most useful things when a large data of the same type need to be processed or manipulated. Collections can be populated and manipulated as whole using ‘BULK’ option in Oracle.
What is Pragma Autonomous_transaction?
The AUTONOMOUS_TRANSACTION pragma changes the way a subprogram works within a transaction. A subprogram marked with this pragma can do SQL operations and commit or roll back those operations, without committing or rolling back the data in the main transaction. … They pass information to the compiler.
Can we write commit in function or trigger or procedure?
Can we have COMMIT inside Trigger? Yes, you can commit inside the trigger. But for this you have to make this trigger transaction to be an Independent transaction from its parent transaction, you can do this by using Pragma.
Why bulk collect is faster in Oracle?
Since the BULK COLLECT fetches the record in BULK, the INTO clause should always contain a collection type variable. The main advantage of using BULK COLLECT is it increases the performance by reducing the interaction between database and PL/SQL engine.
What is the use of limit clause in bulk collect in Oracle?
As LIMIT works as an attribute of the FETCH-INTO statement thus to use it you can add keyword LIMIT followed by a specific numerical digit which will specify the number of rows that the bulk-collect clause will retrieve in one go at the end of FETCH-INTO statement.
How do you debug in PL SQL?
Right-click the PL/SQL object that you want to debug and select Database Tools | Recompile. In the Recompile dialog, select With “debug” option. Click OK.