The differences between stored procedures and triggers are: 1. Stored procedures can use input parameters, but triggers cannot; 2. Stored procedures can return zero or n values, but triggers cannot return values; 3. Transactions can be used in stored procedures, but not triggers.
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Stored procedures and triggers are both very important knowledge in the database. Next, the article will compare the differences between the two through many aspects. It has a certain reference effect and I hope it will be helpful to everyone.
What is a trigger?
A trigger is a process (code segment) that is automatically executed when certain events occur in the tables/views in the database. Triggers are mainly used to maintain integrity in the database. Triggers are also used to enforce business rules, audit changes in the database, and replicate data. The most common triggers are Data Manipulation Language (DML) triggers that fire when data is manipulated. Some database systems support non-data triggers, which fire when data definition language (DDL) events occur. These triggers can be used specifically for auditing. Oracle database system supports schema-level triggers
What is a stored procedure?
Stored procedures are applications that can access relational databases. Typically, stored procedures are used to validate data and control access to the database. If some data processing operations require the execution of multiple SQL statements, such operations are implemented as stored procedures. When calling a stored procedure, you must use the CALL or EXECUTE statement. Stored procedures can return results (such as the results of a SELECT statement). These results can be used by other stored procedures or applications. The language used to write stored procedures usually supports control structures such as if, while, for, etc. Depending on the database system used, multiple languages can be used to implement stored procedures
The difference between stored procedures and triggers
(1) A stored procedure is a set of SQL statements are created and stored in the database. So we can reuse the code over and over again. A trigger is a special stored procedure that is not directly called by the user. When a trigger is created, it is defined to trigger when a specific type of data modification is made to a specific table or column.
(2) Users can use Execute or Exec statements to directly call or execute stored procedures, but cannot directly call or execute triggers. Only the trigger is automatically executed when the relevant event is fired.
(3) Stored procedures can take input parameters, but parameters cannot be used as input in triggers. We cannot pass parameters as input to triggers.
(4) The stored procedure can return zero or n values, but the trigger cannot return a value.
(5) We can use transactions in stored procedures, transaction processing is not allowed in triggers
(6) Stored procedures are usually used to perform user-specified tasks, and triggers are usually used For audit work
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