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 #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 #1897058 by disasm, rteijeiro: Replace "boolean" with "bool" when used as param/return/var type

Issue #2454733 followup by amateescu: Add a user-space case-insensitive collation to the SQLite driver

Issue #2457887 by prateekMehta, stefan.r, rpayanm, alexpott: Use Utility\SafeMarkup class instead of Utility\String for placeholder(), checkPlain(),format() functions

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 #2443659 by daffie, mradcliffe, bzrudi71: PostgreSQL: Fix system\Tests\Entity\FieldSqlStorageTest

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

Issue #2388067 by david_garcia: getQualifiedMapTableName is database specific logic out of the database driver

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

Issue #2428377 by sun, daffie, amateescu: SQLite Schema class is missing use Drupal\Component\Utility\Unicode

This reverts commit d1a9a099.

Issue #2425759 by andypost, jhodgdon: SearchQuery lacks preExecute(), making countQuery() run even when there are problems in prepare step

Issue #2343127 by tadityar, harshil.maradiya, aphickey, bburg, ashutoshmishra: Docblock fixes for core/lib/Drupal/Core/Database/Query

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 #2068655 by Berdir, chx, martin107, longwave, webflo, damiankloip, lokapujya, JacobSanford: Entity fields do not support case sensitive queries

Issue #2226863 by cs_shadow, filijonka, joelpittet, pguillard: Update stale references to theme functions that have been converted to Twig

Issue #1224892 by iaine, lapistano, LinL, jonvk: Duplicate code in mysql/schema.inc (createKeySql = createKeysSqlHelper)