dbConnect() turns emulated prepares off, so every query of the web UI, the
ajax calls and the includes the API runs (config, servers, users,
permissions) is a server-side prepare: prepare, execute and close, three
round trips to the database where one would do. From PHP 8.1, pdo_mysql
returns integers and floats as PHP ints and floats with emulated prepares
too, so values keep the types they have now. Emulate prepares there and keep
server-side prepares on older PHP, where every value would become a string.
Emulated prepares quote parameters bound as strings, which breaks LIMIT ?.
dbQuery() now binds integer values as integers (everything else as strings,
as execute() did), and the log and watch ajax calls cast their validated
offset and limit to int. With emulation, PDO would also run several
statements given in one string; MYSQL_ATTR_MULTI_STATEMENTS is turned off so
that is refused as before. CakePHP's own connection is not changed: it
already uses PDO's default, emulated prepares.
tests/php/test_database_emulated_prepares.php compares every column of every
table read through both kinds of prepare (types and values), checks
aggregates, LIMIT with positional and named integers, string and null
parameters, and that two statements in one string are refused.
