On Sunday, 25 February 2018 at 19:29:59 UTC, kdevel wrote:
On Sunday, 25 February 2018 at 11:46:26 UTC, Denis F wrote:
But it is impossible to convert text :names or '?' into
Postgres's "$1": Postgres isn't knows fields names at start of
a query processing and you can't replace '?' to "$<num>" by
simple 'replace' call - it will need full syntax parsing of
Posgres SQL query because queries can contain EXECUTE
statement (whose purpose is executing dynamic commands).
You don't have to parse the full syntax.
You must if you want to make a replacement correctly for all
types of statements.
Quote from another language (which also supports underscore in
integer literals):
"This language" just drops off supporting of dynamic commands by
using prepared statements for requests with arguments:
"WARNING: DBD::Pg now (as of version 1.40) uses true prepared
statements by sending them to the backend to be prepared by the
Postgres server. Statements that were legal before may no longer
work."
It is trivial to replace any placeholders if you use only
prepared statements, yes. But if you after that try to call
procedure which calls EXECUTE IMMEDIATE command inside it will
fail! How many of your users will understand why this happens?
Also I see too high level of abstraction in DBD::Pg. I am isn't
add prepared statement wrappers into dpq2 because its
implementation depends from async queries handling implementation.
dpq2 is "middle-level" - C calls and classes wrappers over some
of it.
