docs: migration guide #887
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Add newtype wrappers that implement `SerializeRow`/`SerializeCql` if the type wrapped over implements `ValueList`/`Value`. It should be useful when migrating codebases to the new traits gradually so that objects from the unchanged code which only implement the old trait can be passed to the code which was already updated to the new traits.
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| ## Background | ||
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| When executing a statement through the CQL protocol, values for the bind markers are sent in a serialized, untyped form. In order to implement a safer and more robust interface, drivers can the information returned after preparing a statement to check the type of the data provided by the user against the actual types of the bind markers. |
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drivers can the information - did you mean can use?
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Yes - thanks, corrected.
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| If you send simple statements along with non-empty lists of values, the slowdown will be as follows: | ||
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| - For `Session::query`, the driver will optionally prepare the statement before sending it, incurring an additional round-trip. |
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optionally? I think driver is always going to do it
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Hm, yeah, by optional I meant here that it only happens when there are values for the query, but I agree that it's more natural to omit "optional" given the "If you send simple statements..." sentence.
In 0.11, the serialization traits are reworked and some guidance will be needed to adapt the existing code to the new traits. Add a document which explains the reason behind the changes, potential issues to watch for and tools that should make migration easier.
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In 0.11, the serialization traits are reworked and some guidance will be needed to adapt the existing code to the new traits. A document is added which explains the reason behind the changes, potential issues to watch for and tools that should make migration easier.
Additionally, the
ValueListandValueListAdapterhelper types are introduced, which are then mentioned in the migration doc.Pre-review checklist
./docs/source/.Fixes:annotations to PR description.