To switch which mode you're in, you'd use. When you dont, then it is Implicit transaction. When you explicitly specify begin transaction and end transaction then it is called Explicit Transaction. You only need to use an explicit SAVEPOINT if and only if you want to break down a transaction into different groups of statements, with each group being individually undoable within the constraints defined by Db2. Everything in sql server is contained in a transaction. Notice that you do not need to use explicit SAVEPOINTS as shown in your question. Where accnumber = you do not want to use anonymous blocks, then your code can (with autocommit DISABLED) read: commit - if you want to end any previous transaction Update accounts set accbalance = accbalance +50 Update accounts set accbalance = accbalance -50 Data Studio) to use an alternative delimiter to indicate the end of the block (for example, use as the block delimiter), and then you use SQL like this: Or, regardless of autocommit setting, you can use an anonymous block, if you configure your SQL submitting tool (ie. If you want to set the transaction explicitly use: SET TRANSACTION ISOLATION LEVEL READ COMMITTED - but the transaction will be physically created when first row is modified, not when this statement is executed. You can disable autocommit, run both update statements and explicitly COMMIT Normal, read committed transaction, starts automatically with the first modified row. When you want multiple statements to execute atomically then you have these options: You can configure IBM Data Studio (and any other similar tools) to disable autocommit, which then forces you to explicitly use COMMIT or ROLLBACK to end a transaction. Usually autocommit is the default behaviour for such tools, but is configurable. The transaction ends when there is a COMMIT, or a ROLLBACK.īut any COMMIT can either be explicit in your code, or implicit made by the tool that submits the SQL (in this case IBM Data Studio) by autocommit after each line. The transaction begins on the first statement after a previous transaction ends, or after a connect. In Db2-LUW, all statements execute in a transaction, automatically.
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