1Z0-819 JDBC 4

Question 1

What happens if you call `Connection.rollback()` when `autoCommit` is `true`?

Accepted Answer

It throws an SQLException

Answer

Calling `rollback()` when `autoCommit` is `true` throws an `SQLException` because there is no active transaction to roll back.

Question 2

Which `DatabaseMetaData` method retrieves a `ResultSet` of all tables in the connected database?

Accepted Answer

getTables(catalog, schema, tableNamePattern, types)

Answer

`DatabaseMetaData.getTables(catalog, schemaPattern, tableNamePattern, types)` returns a ResultSet describing the tables available in the connected database.

Question 3

Which `SavePoint` feature allows partial rollback within a transaction?

Accepted Answer

Connection.createSavepoint() marks a point you can roll back to without aborting the whole transaction

Answer

`Connection.setSavepoint()` marks an intermediate point in a transaction that you can roll back to with `rollback(savepoint)` while keeping earlier changes.

Question 4

Which `ResultSet` concurrency constant allows updates to be made through the ResultSet object?

Accepted Answer

ResultSet.CONCUR_UPDATABLE

Answer

`ResultSet.CONCUR_UPDATABLE` allows the caller to update rows in the database directly through the ResultSet using update methods.

Question 5

What is the purpose of `DataSource` compared to `DriverManager` in JDBC?

Accepted Answer

DataSource provides connection pooling and is the preferred enterprise approach

Answer

`DataSource` is the preferred way to obtain connections in enterprise applications because it supports connection pooling, improving performance and scalability.

(1Z0-819) Oracle Java SE 11 Developer Practice Test

(1Z0-819) Oracle Java SE 11 Developer Practice Test

1Z0-819 JDBC 4