### Description
1. Fixing issues identified by similarity checker
2. Fix the corresponding sql unit tests
3. Fix JSTests failure due to above changes
4. Fix corresponding C# test failure
----
#### AI description (iteration 1)
#### PR Classification
This pull request is a code cleanup that standardizes and improves error message wording across the codebase.
#### PR Summary
The changes update error messages throughout the repository to provide clearer, more consistent, and more detailed feedback when operations fail.
- Updates in geospatial operator files (e.g. in `$geoNear`, `$near`, `$nearSphere`) replace informal phrasing with precise messages.
- Numerous error messages in aggregation and projection test files have been reworded for consistent phrasing
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
### Does this PR have any customer impact?
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
### Are you introducing any new config? If yes, do you have tests with and without them being set?
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
draft
----
#### AI description (iteration 1)
#### PR Classification
Bug fix: This PR revises error messages and inline comments to improve clarity and consistency across the code and test outputs.
#### PR Summary
The changes refactor and update a large number of error messages across various modules—ranging from aggregation and update operators to geospatial, schema validation, and command handling—to provide more precise diagnostic feedback.
- **Tests (e.g. in `tests/expected/...
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
### Does this PR have any customer impact? No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc) Feature
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes) No
### Are you introducing any new config? If yes, do you have tests with and without them being set? No
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
Support let and `$$NOW` variables with update queries.
The values of the variables can be accessed in the query `q` with `$expr` and 'u' with an aggregation pipeline.
Example:
```
{
update: <collection>,
updates: [
{
q: {$expr: {$eq: ["$_id", "$$varRef"]}},
u: [{$set: {"a": "$$NOW"}}],
multi: false, // updateOne
}
],
let: {"varRef": 1},
...
}
```
We parse the let value (together with the time system variables - $$NOW) and propagate it through the aggregation and variable contexts.
To enable feature, turn on the `EnableVariablesSupportForWriteCommands` GUC.
----
#### AI description (iteration 1)
#### PR Classification
This PR implements a new feature by adding support for the "let" variable specification in update commands.
#### PR Summary
The changes integrate "let" support into update operations, allowing dynamic variable specifications to be applied during update candidate selection, serialization, and execution. This enhancement improves the flexibility and expressiveness of update queries in the engine.
- In `src/commands/update.c`, the code now parses and applies a new `variableSpec` (under the "let" field) when building update queries and managing SQL arguments.
- In `include/infrastructure/documentdb_plan_cache.h`, new plan cache macros are added to account for update candidates using let and collation.
- In `include/commands/update.h`, the `UpdateOneParams` structure is updated to include the `variableSpec` parameter.
- In `src/commands/delete.c`, references to the unsupported "let" field in delete commands are removed.
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
Related work items: #3423115, #3613875
### Does this PR have any customer impact?
Yes
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Perf
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
### ChangeLog (Refer [Template](../oss/CHANGELOG.md))
### Description
Currently for Update/Delete, we currently parse the update spec, query spec, etc into pgbsons on startup. Then reuse it per commands.
This has a few issues - for large document requests, this causes us to duplicate memory and persist it for the duration of the update and also transcode all up front - this is worse for multi-node when all we need to do is build yet another update spec and push it to the worker.
Instead, we now only cache pointers to the spec document; then when we need it we convert to pgbson only if necessary.
A consequence of this is that on a single node update, if we're doing a simple updateOne on _id then we would never serialize the updateSpec at all (for instance).
We also more eagerly free memory on the intermediate update specs.
----
#### AI description (iteration 1)
#### PR Classification
Performance optimization for update parsing by refactoring BSON value handling.
#### PR Summary
This PR streamlines update parsing by replacing heavy BSON initialization routines with lightweight wrappers and converting update-related types from `pgbson*` to `bson_value_t*`, which reduces overhead and improves coordinator/worker compatibility.
- `src/commands/update.c`: Replaced multiple `PgbsonInitFromDocumentBsonValue` and similar calls with efficient wrappers like `CreateBsonValueFrom` and updated serialization (including back-compatible array filter and update document formats).
- `include/commands/update.h`: Updated update structure fields to use `bson_value_t*` instead of `pgbson*`, aligning interfaces with the new parsing approach.
- `src/update/bson_update.c` and `bson_update_operators_workflow.c`: Refactored update type determination and replace document logic to use new BSON value iterators and helper functions.
- Other modules (e.g. `commands/find_and_modify.c`, `commands/delete.c`, query operators, sharding) were updated to leverage the lighter-weight BSON representation and its associated helper routines.
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactoring
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Remove helio from file name
Remove helio references from source content except schema reference
Start local documentdb server with the documentdb extension
Regression tests using the documentdb extension
----
#### AI description (iteration 1)
#### PR Classification
Code cleanup
#### PR Summary
This pull request removes references to "helio" from the `documentdb_core` source code.
- `scripts/utils.sh`: Renamed variables from `preloadExtensions` to `preloadLibraries`.
- `pg_documentdb_core/include/utils/error_utils.h`: Updated function and macro names to replace "Helio" with "DocumentDB".
- `pg_documentdb_core/include/io/helio_bson_core.h` and `pg_documentdb_core/include/query/helio_bson_compare.h`: Moved to `pg_documentdb_core/include/io/bson_core.h` and `pg_documentdb_core/include/query/bson_compare.h`.
- `pg_documentdb_core/src/collation/collation.c` and `pg_documentdb_core/src/io/pgbson.c`: Replaced error codes and messages to use "DocumentDB" instead of "Helio".
- `scripts/validate_helio_extension_state.sh`: Added exceptions for certain files to skip validation for "helio" references.
### Does this PR have any customer impact?
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
### Are you introducing any new config? If yes, do you have tests with and without them being set?
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
[OSS] remove dependencies on helio errors
### Does this PR have any customer impact?
No
### Type (Feature, Refactoring, Bugfix, DevOps, Testing, Perf, etc)
Refactor
### Does it involve schema level changes? (Table, Column, Index, UDF, etc level changes)
No
### Are you introducing any new config? If yes, do you have tests with and without them being set?
No
### Release Note (Refer [Template](../docs/release_notes/pgmongo_template.md))
### Description
Move source files under new directory.
----
#### AI description (iteration 1)
#### PR Classification
Code reorganization
#### PR Summary
This pull request moves the `helio_api` and `helio_distributed` sources under the `documentdb` directory, updating references and initialization logic accordingly.
- Added `pg_documentdb.c` for initializing the `pg_documentdb` extension.
- Added `documentdb_distributed.c` for initializing the `pg_documentdb_distributed` extension.
- Updated `validate_helio_extension_state.sh` to include new checks for `documentdb`.
- Moved `helio_api_extension_version.c` to `documentdb_extension_version.c` without code changes.
- Updated various `Makefile` configurations to reflect the new directory structure and dependencies.
Jinrui Zhang
Xing Fan
Cornelius Boateng
Vinod Sridharan
Zinan Ren
Shuai Tian