Connection (Reactive Relational Database Connectivity

All Superinterfaces:

Closeable
```
public interface Connection
extends Closeable
```
A single connection to a database. SQL statements are executed and results are returned within the context of a connection. A Connection object can consist of any number of transport connections to the underlying database or represent a session over a multiplexed transport connection. For maximum portability, connections should be used synchronously.
Connection objects initiate database conversations for transaction management and statement execution. Objects created by a connection are only valid as long as the connection remains open.
When configuring a connection, R2DBC applications should use the appropriate methods such as beginTransaction(), setAutoCommit(boolean) and setTransactionIsolationLevel(IsolationLevel) to change transaction properties instead. Applications should not execute SQL commands directly to change the connection configuration when a R2DBC method is available.
New connections are by default created in auto-commit mode.

See Also:

Statement, Result, Row

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`Publisher<Void>`	`beginTransaction()` Begins a new transaction.
`Publisher<Void>`	`beginTransaction(TransactionDefinition definition)` Begins a new transaction.
`Publisher<Void>`	`close()` Release any resources held by the `Connection`.
`Publisher<Void>`	`commitTransaction()` Commits the current transaction.
`Batch`	`createBatch()` Creates a new `Batch` instance for building a batched request.
`Publisher<Void>`	`createSavepoint(String name)` Creates a savepoint in the current transaction.
`Statement`	`createStatement(String sql)` Creates a new statement for building a statement-based request.
`ConnectionMetadata`	`getMetadata()` Returns the `ConnectionMetadata` about the product this `Connection` is connected to.
`IsolationLevel`	`getTransactionIsolationLevel()` Returns the `IsolationLevel` for this connection.
`boolean`	`isAutoCommit()` Returns the auto-commit mode for this connection.
`Publisher<Void>`	`releaseSavepoint(String name)` Releases a savepoint in the current transaction.
`Publisher<Void>`	`rollbackTransaction()` Rolls back the current transaction.
`Publisher<Void>`	`rollbackTransactionToSavepoint(String name)` Rolls back to a savepoint in the current transaction.
`Publisher<Void>`	`setAutoCommit(boolean autoCommit)` Configures the auto-commit mode for the current transaction.
`Publisher<Void>`	`setTransactionIsolationLevel(IsolationLevel isolationLevel)` Configures the isolation level for the current transaction.
`Publisher<Boolean>`	`validate(ValidationDepth depth)` Validates the connection according to the given `ValidationDepth`.

- Method Detail
  - beginTransaction
```
Publisher<Void> beginTransaction()
```
    Begins a new transaction. Calling this method disables auto-commit mode.
    
    Returns:
    
    a Publisher that indicates that the transaction is open
  - beginTransaction
```
Publisher<Void> beginTransaction(TransactionDefinition definition)
```
    Begins a new transaction. Calling this method disables auto-commit mode. Beginning the transaction may fail if the TransactionDefinition conflicts with the connection configuration.
    
    Parameters:
    
    definition - attributes for the transaction.
    
    Returns:
    
    a Publisher that indicates that the transaction is open
    
    Since:
    
    0.9
  - close
```
Publisher<Void> close()
```
    Release any resources held by the Connection.
    
    Specified by:
    
    close in interface Closeable
    
    Returns:
    
    a Publisher that termination is complete
  - commitTransaction
```
Publisher<Void> commitTransaction()
```
    Commits the current transaction.
    
    Returns:
    
    a Publisher that indicates that a transaction has been committed
  - createBatch
```
Batch createBatch()
```
    Creates a new Batch instance for building a batched request.
    
    Returns:
    
    a new Batch instance
  - createSavepoint
```
Publisher<Void> createSavepoint(String name)
```
    Creates a savepoint in the current transaction.
    
    Parameters:
    
    name - the name of the savepoint to create
    
    Returns:
    
    a Publisher that indicates that a savepoint has been created
    
    Throws:
    
    IllegalArgumentException - if name is null
    
    UnsupportedOperationException - if savepoints are not supported
  - createStatement
```
Statement createStatement(String sql)
```
    Creates a new statement for building a statement-based request.
    
    Parameters:
    
    sql - the SQL of the statement
    
    Returns:
    
    a new Statement instance
    
    Throws:
    
    IllegalArgumentException - if sql is null
  - isAutoCommit
```
boolean isAutoCommit()
```
    Returns the auto-commit mode for this connection.
    
    Returns:
    
    true if the connection is in auto-commit mode; false otherwise.
  - getMetadata
```
ConnectionMetadata getMetadata()
```
    Returns the ConnectionMetadata about the product this Connection is connected to.
    
    Returns:
    
    the ConnectionMetadata about the product this Connection is connected to
  - getTransactionIsolationLevel
```
IsolationLevel getTransactionIsolationLevel()
```
    Returns the IsolationLevel for this connection.
    Isolation level is typically one of the following constants:
    IsolationLevel is extensible so drivers can return a vendor-specific IsolationLevel.
    Returns:
    
    the IsolationLevel for this connection.
  - releaseSavepoint
```
Publisher<Void> releaseSavepoint(String name)
```
    Releases a savepoint in the current transaction. Calling this for drivers not supporting savepoint release results in a no-op.
    
    Parameters:
    
    name - the name of the savepoint to release
    
    Returns:
    
    a Publisher that indicates that a savepoint has been released
    
    Throws:
    
    IllegalArgumentException - if name is null
  - rollbackTransaction
```
Publisher<Void> rollbackTransaction()
```
    Rolls back the current transaction.
    
    Returns:
    
    a Publisher that indicates that a transaction has been rolled back
  - rollbackTransactionToSavepoint
```
Publisher<Void> rollbackTransactionToSavepoint(String name)
```
    Rolls back to a savepoint in the current transaction.
    
    Parameters:
    
    name - the name of the savepoint to rollback to
    
    Returns:
    
    a Publisher that indicates that a savepoint has been rolled back to
    
    Throws:
    
    IllegalArgumentException - if name is null
    
    UnsupportedOperationException - if savepoints are not supported
  - setAutoCommit
```
Publisher<Void> setAutoCommit(boolean autoCommit)
```
    Configures the auto-commit mode for the current transaction. If a connection is in auto-commit mode, then all Statements will be executed and committed as individual transactions. Otherwise, in explicit transaction mode, transactions have to be started explicitly. A transaction needs to be either committed or rolled back to clean up the transaction state.
    Calling this method during an active transaction and the auto-commit mode is changed, the transaction is committed. Calling this method without changing auto-commit mode this invocation results in a no-op.
    
    Parameters:
    
    autoCommit - the isolation level for this transaction
    
    Returns:
    
    a Publisher that indicates that auto-commit mode has been configured
  - setTransactionIsolationLevel
```
Publisher<Void> setTransactionIsolationLevel(IsolationLevel isolationLevel)
```
    Configures the isolation level for the current transaction.
    Isolation level is typically one of the following constants:
    IsolationLevel is extensible so drivers can accept a vendor-specific IsolationLevel.
    Parameters:
    
    isolationLevel - the isolation level for this transaction
    
    Returns:
    
    a Publisher that indicates that a transaction level has been configured
    
    Throws:
    
    IllegalArgumentException - if isolationLevel is null
  - validate
```
Publisher<Boolean> validate(ValidationDepth depth)
```
    Validates the connection according to the given ValidationDepth. Emits true if the validation was successful or false if the validation failed. Does not emit errors and does not complete empty.
    
    Parameters:
    
    depth - the validation depth
    
    Returns:
    
    a Publisher that indicates whether the validation was successful
    
    Throws:
    
    IllegalArgumentException - if depth is null

Interface Connection

Method Summary

Method Detail

beginTransaction

beginTransaction

close

commitTransaction

createBatch

createSavepoint

createStatement

isAutoCommit

getMetadata

getTransactionIsolationLevel

releaseSavepoint

rollbackTransaction

rollbackTransactionToSavepoint

setAutoCommit

setTransactionIsolationLevel

validate