Issue #2451395 by dawehner: drupal_get_schema()/drupal_get_complete_schema() no longer work as expected; remove them

Issue #2463321 by amateescu: Serializing the database connection is dangerous and error-prone, make it unserializable again

Issue #2389455 by hussainweb, AjitS, Mile23, subhojit777, tibbsa, Ayesh: Clean-up system module test members - ensure property definition and use of camelCase naming convention

Issue #2453311 by David_Rothstein, TravisCarden, Dom., rpayanm: Issue #2417983 follow-up: a few more "the the"s

Issue #2388255 by dawehner, hussainweb, pwolanin: Limit PDO MySQL to executing single statements if PHP supports it

Issue #2428695 by amateescu, daffie: SQLite date handling is wrongly implemented and arguments handling needs override

Issue #1668644 by Island Usurper, phayes, daffie, Brandonian, gease: PostgreSQL: Impossible to change a field to serial, bigserial, or numeric

Issue #1600670 by mradcliffe, bendiy, bzrudi71, andypost, daffie, stefan.r, devpreview: Cannot query Postgres database that has column names with capital letters

Issue #1013034 by bzrudi71, jaredsmith, andypost, alexpott, dbcollies, ncl, jhedstrom, kathyh: PostgreSQL constraints do not get renamed by db_rename_table()

Issue #2401919 by icampana, alexpott, jibran, ParisLiakos, Samshel, xavier.cabrera, alejandrovaras: Fix various file permissions to be 644

Issue #2358079 by pwolanin, Berdir: Require a specific placeholder format in db_query() in order to trigger argument expansion, and require explicit 'IN' parameter for conditions

Issue #2347999 by Mile23, daffie, cs_shadow, cosmicdreams: DrupalUnitTestBase is deprecated, replace with KernelTestBase

Issue #2357311 by penyaskito: Fixed Follow-up to SA-CORE-2014-005 (tests don't work correctly on non-MySQL databases).

Issue #2357249 by Stefan Horst, greggles, larowlan, David_Rothstein, klausi: Fixed SA-CORE-2014-005 (SQL injection).

Issue #2232425 followup by danblack, stefan.r: Fixed Database Schema field/column default value is not properly quoted via PDO::quote().

Issue #2297993 by cilefen, marthinal, ivanjaros: Fixed MySQL column and table comments are not truncated properly.

Issue #1510544 by swentel, Bojhan, Gábor Hojtsy, merlinofchaos, Cottser, Wim Leers, plopesc, aspilicious, sannejanssen,  larowlan, tim.plunkett, nod_: Fixed Show previews in front-end theme, able to select different view modes.

Issue #2284103 by alexpott, fabpot, damiankloip, Xano, Xen, Berdir: Fixed Remove the request from the container.

Issue #2080311 by rhm50, amitgoyal, InternetDevels, Rajesh Ashok, pfrenssen, natemow, areke, chertzog | mrsinguyen: Clean up Drupal\system\Tests\Database\SelectTest.php.

Issue #697760 by sun: Replace getInfo() in tests with native phpDoc + annotations (following PHPUnit).

Issue #2275877 by Mixologic, duellj, Les Lim, Xano, David Strauss: Replace master/slave terminology with primary/replica.

Issue #2080343 by connork, izus, rahul.shinde, lokapujya | mrsinguyen: Remove Unused local variables from system module.