Allowed CStr to be used as SPI commands #1864
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| fn execute( | ||
| /// A trait representing a query which can be prepared. | ||
| pub trait PreparableQuery<'conn>: Query<'conn> { |
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This probably seems obvious but can you explain how this distinguishes from Query?
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To distinguish from the prepared statements which should not be used by the prepare methods of the SPI client.
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Hm, not entirely sure what the benefit is?
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This is probably obvious to you, it's just been ages since I've looked at the Query API and my main dread is it being cemented further, because I would rather it... not exist, tbh. Not in its current form anyway. It's... overly cutesy.
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The problem that trait solves is prohibiting PreparedStatement<'conn> from being used with prepare and prepare_mut methods of the SqlClient<'conn>, so the following code will result in a compiler error:
let conn = SpiConnection::connect()?;
let client = conn.client();
let once = client.prepare(c"SELECT 1", None)?;
let twice = client.prepare(once, None);
// ------- ^^^^ the trait `PreparableQuery<'_>` is not implemented for `PreparedStatement<'_>`
// |
// required by a bound introduced by this callThere was a problem hiding this comment.
I played with the CI and observed that my UI test fails only for PostgreSQL versions 12, 13 and 14, but not for others. That's totally weird. See #1870.
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...oh, I remember. They introduced a type named String in PostgreSQL. Can you defer the test to opening an issue instead?
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This one, right? https://doxygen.postgresql.org/structString.html
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Thank you~! |
Made with love to those who doesn't like allocations ❤️
Since the Rust version 1.77 there's a possibility to use
candcrprefixes to make C string literals. That requires a little bit more characters to type, but reduces the number of allocations and therefore boostspgrxextensions opted in. The feature isn't breaking due to being generic based.