Blocking
Utility class to use connections given by the ConnectionSupplier.
Use Database if you use Kotlin.
Nested transaction
Nested transactions are transactions that use an existing connection, enabling you to, for example, have a [transactional] inside another.They are supported on methods that use callbacks.
Nested transaction block Queries executed in a nested transaction are not committed when exiting the block, only top-level transactions do. Read-only status A nested transaction cannot be created if the existing connection is read-only and the nested transaction is read-write.- ✓ Read-write -> Read-only
- ✓ Read-only -> Read-only
- ✗ Read-only -> Read-write
Tracing
The connection could be wrapped depending on the configuration, for example, to log the queries (in which case a ParametrizedQuery is used), as well as timing them.A SQL statement is traced if any of these conditions is met:
- getLogQueries is enabled, and the logger of the class that created the prepared statement has its
TRACElogs enabled. - getQueryLogThreshold is configured
The logged SQL statements will use the logger of the class that created the prepared statement. If a utility class creates statements, you should use @IgnoreStackFrame, which will instead take the logger of the class that called your utility class. You can also use withLogger if you wish to use a different logger.
Batching support
If you must run a lot of DML statements (INSERT, UPDATE, ...), you can batch them as to execute all of them in one go, massively improving performances on larger updates. For that, you can use any function giving you a prepared statement, then, you can add statements by:
- Adding the parameters using setParameters
- Calling BlockingPreparedStatement#addBatch()
Repeat those two steps for all your statements, then call executeBatch to run all of them.
Note: To read returned columns (like an INSERT INTO ... RETURNING {column} in PostgreSQL), you must specify the column indexes/names when creating your statement, and read them back from getGeneratedKeys.