disable savepoints by default, added dedicated getter/setter to enable/disable, added exceptions when trying to use savepoints when not supported by the platform

disable savepoints by default, added dedicated getter/setter to enable/disable, added exceptions when trying to use savepoints when not supported by the platform

DBAL-54 - Fix sequence drop executed before tables, however sequences mostly depend on tables. Also clean up several test-failures on MSSQL tests and  Oracle Index detection.

DBAL-50 - Explicitly add an index for each foreign key added to a Schema\Table instance. Removed code to FixSchema based on foreign keys, since assumptions now dont apply anymore. Refactored algorithms to check for duplicate or potential overrule indexes into Schema\Index classes, added tests and unified Table API handling these conflicts

Fix bug in Oracle Schema/Platform detection of DateTime vs DateTimeTz type and disable a logging test that breaky MySQL testsuite.

DBAL-39 - Changed SQLLogger again, the recent change disallows to log a failed query, however adding a lastexecuted query would add additional overhead (last params and types would be needed to). So now each logger has a startQuery() and a stopQuery() method. Additionally the logger now gets passed the array of types.

DBAL-37 - Fix PostgreSQL Platform not supporting changes in Autoicnrement during ALTER TABLE generation

DBAL-11 - Changed Interface of SQLLogger to allow for timing variables, added tests for logging. Contract of Loggers changed, they are not called before the query but after the query they are logging, which means queries that fail wont appear in the logs.

DBAL-21 - Fallback for Domain Types to underyling db types when matching against Doctrine Mapping typesin Postgres Platform/SchemaManager

DBAL-22 - Make DateTime type the fallback for platforms not supporting DateTimeTz, add test for the later and test for default DateTimeZone

DBAL-22 - Fix DateTime with Timezone handling in Postgres and Oracle by introducing new type DateTimeTz and have SchemaManagers of both platforms detect this type. Added general conversion testcase which made some bugs in Oracle Date Handling and $stmt->fetchColumn() appear

Fixed a problem in PostgreSql AutoIncrement Detection, changed Autoincrement API for platform/schema manager interaction a little bit

Added a bunch of functional tests for the public read, write and transactional public DBAL API, passing all the current drivers

Added a Write Test

Removed EntityTransaction until it has a real purpose. Added the affected entity to OptimisticLockException. Updated functional optimistic locking tests accordingly.

Revertd partially the support to DBAL\Transaction, it was wrong. Fixed implementation of ORM\EntityTransaction and fixed tests.

DDC-496 Finished first versions of platform and schema manager for DB2, DDC-528 Added support for PDO_IBM driver, passing all but 3 tests that are related to CLOB fields

[2.0][DDC-354][DDC-425] Fixed. Encapsulated SQL logging better in the DBAL. Added binding types to DBAL mapping types as well as using these binding types in the persisters. Query and NativeQuery now support PDO binding types as well as DBAL mapping types when binding parameters.

[2.0] Refactored Doctrine\DBAL\Schema API a bit Table::createColumn() was inconsistent with all the other methods being add*