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This article mainly explains "what are the basic transaction commands of commonly used relational databases". Interested friends may wish to take a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn what are the basic transaction commands of a commonly used relational database.

Introduction to basic transaction commands

Description: in command

| (vertical bar) separate syntax items in parentheses or curly braces. Only one of them can be used.

[] (square brackets) optional grammar items. Do not type square brackets.

{} (curly braces) required grammar items. Do not type curly braces.

SQLSERVER

1) BEGIN {TRAN | TRANSACTION} [{transaction_name | @ tran_name_variable} [WITHMARK ['description']] [;]

Indicates that a local transaction with a value named transaction_name or @ tran_name_variable is explicitly opened.

2) BEGINDISTRIBUTED {TRAN | TRANSACTION} [transaction_name | @ tran_name_variable] [;]

Means to explicitly open a distributed transaction with a value named transaction_name or @ tran_name_variable

3) COMMIT [{TRAN | TRANSACTION} [transaction_name | @ tran_name_variable]] [WITH (DELAYED_DURABILITY= {OFF | ON})] [;]

Indicates that the transaction is committed and the transaction is released to use resources, and all data changes since the beginning of the transaction become a permanent part of the database. The contents in square brackets can be omitted, so the commit of COMMIT transactions is the same as COMMITTRANSACTION.

4) COMMIT [WORK] [;]

Commit and end the transaction. The same functionality as COMMITTRANSACTION, but COMMITTRANSACTION accepts the specified transaction name. This syntax is compatible with SQL-92.

5) ROLLBACK {TRAN | TRANSACTION} [transaction_name | @ tran_name_variable | savepoint_name | @ savepoint_variable] [;]

Means to roll back the transaction to the starting point or specify a SavePoint to clear all data changes from the starting point of the transaction to a SavePoint and release related resources. The contents in square brackets can be omitted, and the rollback of ROLLBACK transactions has the same function as ROLLBACKTRANSACTION.

6) ROLLBACK [WORK] [;]

Roll back the transaction to the starting point of the transaction. The same functionality as ROLLBACKTRANSACTION, but ROLLBACKTRANSACTION can specify a transaction name. This ROLLBACK is compliant with the ISO standard.

When nesting transactions, ROLLBACKWORK always rolls back to the farthest BEGINTRANSACTION statement and reduces the @ @ TRANCOUNT system function to 0

7) SAVE {TRAN | TRANSACTION} {savepoint_name | @ savepoint_variable} [;]

Set the transaction save point within the transaction. Savepoint_name is the name assigned to the SavePoint. Savepoint_variable is the name of a user-defined variable that contains a valid save point name.

8) SETTRANSACTIONISOLATIONLEVEL {READUNCOMMITTED | READCOMMITTED | REPEATABLEREAD | SNAPSHOT | SERIALIZABLE}

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