In AS ABAP, database commits are triggered either implicitly or explicitly.
A database commit closes all opened
database cursors. It is particularly important that database commits are not triggered (in one of
the ways listed here) in
loops and after the statement
Implicit Database Commits
The implicit database commits in an AS ABAP are caused by the fact that an AS ABAP uses its own work processes to connect to the database system. A work process can only ever execute a single database LUW but cannot interfere with the database LUWs belonging to other work processes. Since an ABAP program can be executed by different work processes during its runtime, the database LUW for the current work process must be completed each time an action takes place that leads to a change of work process. As a result, a database commit is performed implicitly in the following situation:
- Completion of a dialog step
The program waits for a user action and does not occupy a work process during this time. The next free work process is assigned to the program in the next dialog step.
- Calling a function module in a synchronous or
asynchronous remote function call
The current work process passes control to a different work process or system. An exception to this are updates. When updates are running, sRFC and aRFC do not cause work processes to be switched or database commits to be executed.
- Completion of a function module called in a separate work process using a synchronous remote function call.
Usually, a new work process is allocated to the call program. If a new sRFC follows quickly enough, and enough free work processes exist, the work process sRFC continues to be used, but an implicit database commit is performed regardless.
- Execution of the statement
RECEIVEin a callback routine specified in an asynchronous RFC
To receive data from another AS Instance, the current work process must be interrupted before the callback routine is executed A database commit is performed, except during the update.
- HTTP/HTTPS/SMTP communication executed using Internet Communication Framework
A database commit is executed before each response is sent in an ICF server program or ICF client program. An exception to this are updates. This behavior applies regardless of whether the communication is stateless or stateful.
- Receiving messages from ABAP messaging channels
A database commit is executed while the methods START_MESSAGE_DELIVERY and STOP_MESSAGE_DELIVERY of a consumer object are being executed.
- WebSocket or TCP communication using ABAP Push Channels
Each time a message is sent and each time APC processing is exited, a database commit is executed. An exception to this are updates. More specifically, the methods BIND_AMC_MESSAGE_CONSUMER and UNBIND_AMC_MESSAGE_CONSUMER (for binding an ABAP messaging channel) produce a database commit.
- Current work process interrupted using the statement
WAIT UP TO, WAIT FOR ASYNCHRONOUS
WAIT FOR MESSAGING CHANNELS.
After the interruption, the program is allocated the next free work process. An exception to this are updates.
- Sending error messages,
information messages, and warnings.
These messages interrupt the current dialog step (see above).
The implicit database commit takes place on all currently open database connections of the current work process. The situations above cause a work process to be switched while a program is running, but it is also possible for entire programs to be executed in a different work process, such as when a program is called in a background work process in background processing. Here, a database commit is also made when the work process is switched.
- When an internal session is exited, there is no implicit database commit on the standard connection and there is no database rollback. This must be programmed explicitly if required.
- If (in the case of implicit database commits) a
global temporary table filled using ABAP
SQL statements is not emptied by an explicit database commit or database rollback or by the statement
WHEREcondition, the runtime error COMMIT_GTT_ERROR occurs.
Explicit Database Commits
Database commits can be triggered explicitly in ABAP programs in the following ways:
- The relevant database-specific Native SQL statement is used.
- In ADBC, only the method COMMIT of the class CL_SQL_CONNECTION can be used to do this. In other cases, the database interface does not detect the end of the transaction and might not be able to perform certain actions.
COMMITstatement embedded statically between
ENDEXECis detected by the database interface and any required actions performed.
- Executing the ABAP SQL
COMMIT CONNECTION. The database commit takes place on the specified database connection.
- Calling the function module DB_COMMIT. This function module encapsulates the corresponding Native SQL statement. By default, the database commit is triggered on the
connection currently open for
EXEC SQL. The commit is triggered explicitly on the standard connection by passing the value of
abap_trueto the input parameter IV_DEFAULT. The function module DB_COMMIT raises the event DB_TRANSACTION_FINISHED of the class CL_DBI_TRANSACTION_STATE, which is handled by the application log framework.
- Executing the ABAP SQL
COMMIT CONNECTION. The database commit takes place on all currently open database connections. The statement
COMMIT WORKalso closes the current SAP LUW and performs the associated actions.
COMMIT statements are not allowed in AMDP methods.
- A simple database commit in an ABAP program is generally done using the statement
COMMIT CONNECTION(the standard connection can be specified here using
default). The database LUW can be monitored by the application log by using the function module DB_COMMIT. Apart from the database commit itself, using the statement
COMMIT WORKalso has certain other consequences with respect to the SAP LUW.
- All the methods specified here for explicit database commits empty global temporary tables and prevent the runtime error COMMIT_GTT_ERROR in the case of implicit database commits.
Database Commit on Secondary Connections
Implicit deactivations of a secondary connection or a service connection at the end of an internal session trigger a database commit in the transaction context of this database connection. For more information, see Database Connections.