MDEV-25529 Auto-create: Pre-existing historical data is not partitioned as specified by ALTER by midenok · Pull Request #4938 · MariaDB/server

midenok · 2026-04-14T11:21:58Z

Adds logic into prep_alter_part_table() for AUTO to check the history
range (vers_get_history_range()) and based on (max_ts - min_ts)
difference compute the number of created partitions and set STARTS
value to round down min_ts value (vers_set_starts()) if it was not
specified by user or if the user specified it incorrectly. In the
latter case it will print warning about wrongly specified user value.

In case of fast ALTER TABLE, f.ex. when partitioning already exists,
the above logic is ignored unless FORCE clause is specified. When user
specifies partition list explicitly the above logic is ignored even
with FORCE clause.

vers_get_history_range() detects if the index can be used for row_end
min/max stats and if so it gets it with ha_index_first() and
HA_READ_BEFORE_KEY (as it must ignore current data). Otherwise it does
table scan to read the stats. There is test_mdev-25529 debug keyword
to check the both and compare results. A warning is printed if the
algorithm uses slow scan.

Field_vers_trx_id::get_timestamp() is implemented for TRX_ID based
versioning to get epoch value. It works in vers_get_history_range()
but since partitioning is not enabled for TRX_ID versioning create
temporary table fails with error, requiring timestamp-based system
fields. This method will be useful when partitioning will be enabled
for TRX_ID which is mostly performance problems to solve.

Static key_cmp was renamed to key_eq to resolve compilation after
key.h was included as key_cmp was already declared there.

CLAassistant · 2026-04-14T11:22:07Z

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Copilot

Pull request overview

This PR addresses MDEV-25529 by improving ALTER TABLE behavior for system-versioned tables so that auto-created SYSTEM_TIME partitions correctly account for pre-existing historical rows, and by expanding supported FORCE/partitioning syntax while adding more informative warnings.

Changes:

Add logic to compute the historical timestamp range (min/max) and derive an appropriate number of history partitions during ALTER with AUTO partitioning.
Improve ALTER TABLE grammar to accept additional ordering of FORCE, PARTITION BY ..., and REMOVE PARTITIONING.
Introduce my_timespec_t utilities and new warnings/messages, plus add regression coverage in versioning/partition test suites.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
sql/table.h	Declares `TABLE::vers_get_history_range()` helper.
sql/sql_table.cc	Implements history-range detection using either an index on ROW END or a scan fallback.
sql/sql_partition.cc	Uses history-range data to adjust AUTO-created versioning partitions during ALTER.
sql/partition_info.h / sql/partition_info.cc	Tracks whether STARTS was explicitly specified; factors out STARTS rounding into `vers_set_starts()`.
include/my_time.h	Introduces `my_timespec_t`, comparisons, and min/max sentinels.
sql/sql_class.h / sql/sql_class.cc	Adds THD timestamp formatting helper and `TimestampString` wrapper for warnings.
sql/sql_type.h / sql/sql_type.cc	Adds `Temporal_hybrid` constructor from `my_timespec_t`.
sql/sql_time.h / sql/sql_time.cc	Replaces COMBINE macro with reusable `interval2sec/interval2usec` helpers.
sql/sql_yacc.yy	Extends ALTER TABLE grammar to accept additional FORCE/partitioning command orderings.
sql/share/errmsg-utf8.txt	Renames/extends warning text and adds new warning identifiers for versioning partition behavior.
sql/field.h / sql/field.cc	Adds `Field_vers_trx_id::get_timestamp(pos, sec_part)` implementation for TRX_ID-based versioning fields.
sql/event_data_objects.cc	Expands doc comment for next-time computation with interval/timezone/DST context.
mysql-test/suite/versioning/t/partition2.test + result	Adds regression test coverage for MDEV-25529 and related warnings.
mysql-test/suite/versioning/r/partition.result	Updates expected warning text output.
mysql-test/main/partition.test + result	Adds coverage for improved FORCE/partitioning syntax parsing.

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include/my_time.h

sql/field.cc

sql/sql_partition.cc

sql/sql_table.cc

sql/field.cc

sql/sql_partition.cc

sql/sql_table.cc

Copilot

Pull request overview

This PR improves ALTER TABLE behavior for SYSTEM_TIME partitioning with AUTO by detecting the existing historical data range and auto-adjusting STARTS/partition count so that pre-existing history is partitioned as intended. It also refines FORCE syntax parsing, adds new warning messages, and introduces helper utilities for timestamp/time conversions plus regression tests.

Changes:

Add TABLE::vers_get_history_range() to compute min/max history timestamps (index-based when possible, else scan with warning) and use it during AUTO partition preparation to set STARTS/partition count.
Improve ALTER TABLE ... FORCE syntax handling in the parser and update warning messages (more informative STARTS warning + new warnings).
Add new tests covering MDEV-25529 scenarios (AUTO/FORCE behavior, warnings, slow-scan path, TRX_ID versioning rejection).

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
sql/table.h	Declares `TABLE::vers_get_history_range()` for versioned+partitioned logic.
sql/sql_table.cc	Implements history range detection using index-first/HA_READ_BEFORE_KEY or table scan with warning.
sql/sql_partition.cc	Uses history range during ALTER PARTITION AUTO to correct STARTS and compute required partition count.
sql/sql_yacc.yy	Extends ALTER TABLE grammar to support improved FORCE positioning.
sql/partition_info.h	Adds `starts_clause` flag and declares `vers_set_starts()`.
sql/partition_info.cc	Tracks explicit STARTS clause, factors out STARTS rounding into `vers_set_starts()`, and tweaks default partition setup error handling.
sql/sql_class.h / sql/sql_class.cc	Adds timestamp-to-string helpers and `TimestampString` wrapper for warning formatting.
sql/sql_type.h / sql/sql_type.cc	Adds `Temporal_hybrid(THD*, my_timespec_t)` ctor for timestamp formatting.
sql/sql_time.h / sql/sql_time.cc	Adds reusable interval-to-seconds/microseconds helpers and uses them in interval addition code.
include/my_time.h	Introduces `my_timespec_t` plus comparison helpers/operators and min/max sentinels.
sql/field.h / sql/field.cc	Adds `Field_vers_trx_id::get_timestamp()` to obtain commit timestamp epoch seconds for TRX_ID versioning.
sql/share/errmsg-utf8.txt	Renames/extends STARTS warning and adds new warnings for wrong STARTS and slow ROW END scan.
mysql-test/*	Adds new versioning partition test + updates expected results for warning text changes.

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include/my_time.h

sql/sql_partition.cc

sql/partition_info.cc

sql/field.cc

Copilot

Pull request overview

This PR improves ALTER TABLE ... PARTITION BY SYSTEM_TIME ... AUTO for system-versioned tables by auto-adjusting STARTS and the number of generated history partitions based on pre-existing history data, and by extending parser support for FORCE placement.

Changes:

Add history range detection (TABLE::vers_get_history_range) to drive AUTO partition creation (including warning paths for slow scans).
Add helper logic to round/adjust STARTS (partition_info::vers_set_starts) and emit new warnings when user-provided STARTS is inconsistent with history/query time.
Extend ALTER TABLE grammar for FORCE + partitioning syntax and add/adjust test coverage and expected results.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
sql/table.h	Exposes `TABLE::vers_get_history_range()` for partitioning logic.
sql/sql_table.cc	Implements `TABLE::vers_get_history_range()` using index-first/scan fallback and emits warnings.
sql/sql_partition.cc	Uses history range to recompute AUTO history partition count/STARTS; adds `vers_calc_hist_parts()`.
sql/partition_info.h	Tracks whether `STARTS` was explicitly specified; adds `vers_set_starts()` API.
sql/partition_info.cc	Implements `vers_set_starts()` and updates interval/STARTS warning behavior.
sql/sql_yacc.yy	Accepts additional ALTER TABLE partitioning command orderings (FORCE syntax improvements).
include/my_time.h	Introduces `my_timespec_t` + comparisons and MIN/MAX constants.
sql/sql_type.h / sql/sql_type.cc	Adds `Temporal_hybrid(THD*, my_timespec_t)` constructor used for formatting.
sql/sql_class.h / sql/sql_class.cc	Adds `THD::timestamp_to_string()` and `TimestampString` helper for warnings.
sql/sql_time.h / sql/sql_time.cc	Replaces COMBINE macro with `interval2sec/interval2usec` helpers for interval math.
sql/field.h / sql/field.cc	Implements `Field_vers_trx_id::get_timestamp()` (future TRX_ID work; used by history scanning infra).
sql/share/errmsg-utf8.txt	Adds new warnings (`WARN_VERS_*`) and updates message text to include timestamps.
sql/event_data_objects.cc	Expands function comment (doc clarification).
mysql-test/suite/versioning/t/partition2.test	Adds new regression tests for MDEV-25529 behavior.
mysql-test/suite/versioning/r/partition2.result	Expected output for the new versioning partition tests.
mysql-test/suite/versioning/r/partition.result	Updates expected warning text format.
mysql-test/main/partition.test	Adds tests validating improved ALTER TABLE FORCE syntax.
mysql-test/main/partition.result	Expected output for FORCE syntax tests.

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sql/sql_partition.cc

sql/sql_class.h

Copilot

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds support for AUTO history partition creation during ALTER TABLE ... PARTITION BY SYSTEM_TIME by detecting existing historical timestamp range and adjusting STARTS/partition count accordingly, along with improved FORCE placement in ALTER syntax and new warnings/tests.

Changes:

Implement history-range detection (TABLE::vers_get_history_range) to drive AUTO partition creation and STARTS correction.
Add helper time/timestamp utilities (my_timespec type, interval helpers, timestamp-to-string) and new warnings for user feedback.
Extend SQL grammar and add regression tests covering FORCE syntax and versioning partition AUTO behaviors.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
sql/table.h	Declares `TABLE::vers_get_history_range()` API for partitioning/versioning logic.
sql/sql_yacc.yy	Expands ALTER TABLE grammar to allow `partitioning/remove partitioning` before `alter_list` (FORCE syntax improvements).
sql/sql_type.h	Adds `Temporal_hybrid` ctor from `my_timespec_t` for timestamp formatting.
sql/sql_type.cc	Implements new `Temporal_hybrid(THD*, my_timespec_t)` constructor.
sql/sql_time.h	Introduces `interval2sec()` / `interval2usec()` helpers used by interval arithmetic.
sql/sql_time.cc	Switches date interval arithmetic to the new interval helpers (removes local COMBINE macro).
sql/sql_table.cc	Includes key handling header and renames comparator to avoid collision; adds `TABLE::vers_get_history_range()` implementation.
sql/sql_partition.cc	Adds AUTO history partition calculation and wiring into ALTER partition preparation.
sql/sql_class.h	Adds `THD::timestamp_to_string()` and `TimestampString` helper for warning formatting.
sql/sql_class.cc	Implements `THD::timestamp_to_string()`.
sql/share/errmsg-utf8.txt	Adds/renames warnings for STARTS beyond query time, wrong STARTS, and slow scan.
sql/partition_info.h	Tracks whether STARTS was explicitly specified and exposes `vers_set_starts()`.
sql/partition_info.cc	Implements `vers_set_starts()`, improves OOM error path, and sets `starts_clause`.
sql/field.h	Declares `Field_vers_trx_id::get_timestamp()` override.
sql/field.cc	Implements TRX_ID-based `get_timestamp()` for future TRX_ID versioning support.
sql/event_data_objects.cc	Clarifies documentation for interval scheduling behavior.
mysql-test/suite/versioning/t/partition2.test	Adds new test coverage for MDEV-25529 auto partitioning + FORCE behaviors.
mysql-test/suite/versioning/r/partition2.result	Captures expected results/warnings for the new versioning partition tests.
mysql-test/suite/versioning/r/partition.result	Updates expected warning text due to improved STARTS warning message.
mysql-test/main/partition.test	Adds tests for ALTER TABLE FORCE syntax placements.
mysql-test/main/partition.result	Captures expected output/errors for new FORCE syntax tests.
include/my_time.h	Adds `my_timespec_t` and comparison helpers/operators for timestamp ranges.

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sql/sql_partition.cc

sql/sql_class.cc

include/my_time.h

sql/sql_partition.cc

sql/field.cc

Improves ALTER TABLE syntax when alter_list can be supplied alongside a partitioning expression, so that they can appear in any order. This is particularly useful for the FORCE clause when adding it to an existing command. Also improves handling of AUTO with FORCE, so that AUTO FORCE specified together provides more consistent syntax, which is used by this task in further commits.

…ed as specified by ALTER Adds logic into prep_alter_part_table() for AUTO to check the history range (vers_get_history_range()) and based on (max_ts - min_ts) difference compute the number of created partitions and set STARTS value to round down min_ts value (vers_set_starts()) if it was not specified by user or if the user specified it incorrectly. In the latter case it will print warning about wrongly specified user value. In case of fast ALTER TABLE, f.ex. when partitioning already exists, the above logic is ignored unless FORCE clause is specified. When user specifies partition list explicitly the above logic is ignored even with FORCE clause. vers_get_history_range() detects if the index can be used for row_end min/max stats and if so it gets it with ha_index_first() and HA_READ_BEFORE_KEY (as it must ignore current data). Otherwise it does table scan to read the stats. There is test_mdev-25529 debug keyword to check the both and compare results. A warning is printed if the algorithm uses slow scan. Field_vers_trx_id::get_timestamp() is implemented for TRX_ID based versioning to get epoch value. It works in vers_get_history_range() but since partitioning is not enabled for TRX_ID versioning create temporary table fails with error, requiring timestamp-based system fields. This method will be useful when partitioning will be enabled for TRX_ID which is mostly performance problems to solve. Static key_cmp was renamed to key_eq to resolve compilation after key.h was included as key_cmp was already declared there.

Copilot

Pull request overview

This PR enhances SYSTEM_TIME partitioning AUTO behavior during ALTER TABLE so that existing historical rows are partitioned according to the requested interval/STARTS settings, and expands parser support for FORCE placement in ALTER TABLE partitioning clauses.

Changes:

Add TABLE::vers_get_history_range() to detect historical min/max ROW END timestamps (index-based when possible, otherwise scan with warning) and use it to auto-size partitions and auto-adjust STARTS for history.
Extend ALTER TABLE grammar to allow FORCE-style partitioning/removal syntax variants (partitioning/removal before or after alter_list).
Add new warnings/messages and extensive MTR coverage for AUTO/FORCE/history edge cases.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
sql/table.h	Declares `TABLE::vers_get_history_range()` API.
sql/sql_table.cc	Implements `vers_get_history_range()` and resolves `key_cmp` naming conflict.
sql/sql_partition.cc	Uses history range to compute AUTO partition count and to correct/derive STARTS (with warnings); adds `vers_calc_hist_parts()`.
sql/partition_info.h	Adds `starts_clause` tracking and `vers_set_starts()` declaration.
sql/partition_info.cc	Tracks explicit STARTS clause, factors out STARTS rounding into `vers_set_starts()`, and improves OOM error path in default partition setup.
include/my_time.h	Introduces `my_timespec_t` plus min/max sentinels and comparisons.
sql/sql_type.h	Declares `Temporal_hybrid(THD*, my_timespec_t)` ctor.
sql/sql_type.cc	Implements `Temporal_hybrid` ctor from `(sec,usec)` for formatting.
sql/sql_class.h	Adds `THD::timestamp_to_string()` overloads and `TimestampString` helper.
sql/sql_class.cc	Implements `THD::timestamp_to_string()`.
sql/sql_time.h	Adds `interval2sec()` / `interval2usec()` helpers.
sql/sql_time.cc	Uses `interval2usec()` instead of local COMBINE macro.
sql/sql_yacc.yy	Allows partitioning/removal clauses to appear before/after `alter_list` to support improved FORCE syntax.
sql/share/errmsg-utf8.txt	Renames/extends STARTS warning text and adds new versioning partitioning warnings.
sql/field.h	Declares `Field_vers_trx_id::get_timestamp()` override.
sql/field.cc	Implements `Field_vers_trx_id::get_timestamp()` for TRX_ID versioning.
sql/event_data_objects.cc	Expands comment explaining interval scheduling logic.
mysql-test/suite/versioning/t/partition2.test	New test suite covering AUTO/FORCE/history range behavior and warnings.
mysql-test/suite/versioning/r/partition2.result	Expected results for new versioning partition AUTO tests.
mysql-test/suite/versioning/r/partition.result	Updates expected warning text for STARTS beyond query timestamp.
mysql-test/main/partition.test	Adds tests for improved `ALTER TABLE ... FORCE` partitioning syntax acceptance/rejection.
mysql-test/main/partition.result	Expected output for new FORCE syntax tests.

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sql/sql_table.cc

sql/sql_partition.cc

sql/sql_class.h

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Pull request overview

This PR improves ALTER TABLE ... PARTITION BY SYSTEM_TIME ... AUTO for system-versioned tables by detecting the existing history range and auto-adjusting STARTS/partition count so pre-existing historical rows end up in the intended partitions. It also adds supporting utilities (timestamp formatting, interval helpers), warning messages, and test coverage (including grammar updates for FORCE placement).

Changes:

Add TABLE::vers_get_history_range() to compute min/max historical ROW END using an index when possible (fallback to scan with a warning).
Enhance AUTO partitioning alter flow to recompute STARTS/partition count based on history range (with warnings for user-specified mismatches and slow scan).
Add tests for MDEV-25529 behavior and improved ALTER TABLE ... FORCE syntax permutations.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
`sql/table.h`	Declares `TABLE::vers_get_history_range()` for partition/versioning logic.
`sql/sql_yacc.yy`	Extends ALTER grammar to allow partitioning/remove-partitioning clauses before/after `alter_list` (supports FORCE syntax variants).
`sql/sql_type.h`	Adds `Temporal_hybrid(THD*, my_timespec_t)` constructor declaration.
`sql/sql_type.cc`	Implements the new `Temporal_hybrid` constructor for timespec inputs.
`sql/sql_time.h`	Introduces `interval2sec()` / `interval2usec()` helpers used in interval math.
`sql/sql_time.cc`	Replaces local COMBINE macro usage with shared interval helpers.
`sql/sql_table.cc`	Includes `key.h`, renames `key_cmp`→`key_eq`, and adds `TABLE::vers_get_history_range()` implementation.
`sql/sql_partition.cc`	Adds AUTO history-partition recalculation based on detected history range; adds `vers_calc_hist_parts()`.
`sql/sql_class.h`	Adds `THD::timestamp_to_string()` and `TimestampString` helper for warning formatting.
`sql/sql_class.cc`	Implements `THD::timestamp_to_string()`.
`sql/share/errmsg-utf8.txt`	Renames/updates STARTS warning text and adds new warnings for wrong STARTS and slow scan.
`sql/partition_info.h`	Adds `starts_clause` tracking and declares `partition_info::vers_set_starts()`.
`sql/partition_info.cc`	Tracks STARTS clause presence, refactors STARTS rounding into `vers_set_starts()`, and adds OOM error on default partition element allocation failure.
`sql/field.h`	Declares `Field_vers_trx_id::get_timestamp()` override.
`sql/field.cc`	Implements `Field_vers_trx_id::get_timestamp()` for TRX_ID-based versioning timestamp lookup.
`sql/event_data_objects.cc`	Expands doc comment for next-time computation to clarify semantics.
`mysql-test/suite/versioning/t/partition2.test`	Adds new regression test suite for MDEV-25529, including debug-only index-vs-scan validation.
`mysql-test/suite/versioning/r/partition2.result`	Expected output for the new versioning partition AUTO behavior and warnings.
`mysql-test/suite/versioning/r/partition.result`	Updates expected STARTS warning text to include timestamps.
`mysql-test/main/partition.test`	Adds coverage for improved `ALTER TABLE ... FORCE` syntax permutations.
`mysql-test/main/partition.result`	Expected output for the new FORCE syntax tests.
`include/my_time.h`	Introduces `my_timespec_t` and comparison helpers/operators plus min/max sentinels.

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sql/sql_table.cc

sql/sql_partition.cc

sql/share/errmsg-utf8.txt

sql/sql_partition.cc

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Pull request overview

This PR enhances system-versioned table partitioning so that ALTER TABLE ... PARTITION BY SYSTEM_TIME ... AUTO can auto-create an appropriate number of history partitions based on pre-existing historical data, and also improves related diagnostics and syntax support.

Changes:

Add history-range detection (TABLE::vers_get_history_range) that uses a ROW END-leading index when available (or falls back to a scan with a warning) and uses this range to size AUTO-created history partitions during ALTER.
Introduce STARTS handling improvements (including rounding via vers_set_starts() and new warnings when user-specified STARTS is “wrong” for existing history).
Improve ALTER TABLE grammar to accept FORCE with partitioning/removal earlier in the command, and add comprehensive MTR coverage.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
`sql/table.h`	Declares `TABLE::vers_get_history_range()` for partitioning/versioning logic.
`sql/sql_table.cc`	Implements `vers_get_history_range()` and resolves a name collision by renaming `key_cmp` to `key_eq`.
`sql/sql_partition.cc`	Uses detected history range to compute AUTO history partitions and adjusts `STARTS` when needed.
`sql/partition_info.h`	Adds `starts_clause` tracking and declares `vers_set_starts()`.
`sql/partition_info.cc`	Implements `vers_set_starts()` and updates STARTS warning behavior/message; sets `starts_clause`.
`sql/sql_yacc.yy`	Extends ALTER TABLE grammar to allow partitioning/removal clauses before/after alter_list (FORCE syntax improvements).
`sql/sql_time.h` / `sql/sql_time.cc`	Replaces a macro with reusable `interval2sec()`/`interval2usec()` helpers and updates interval math call sites.
`sql/sql_type.h` / `sql/sql_type.cc`	Adds `Temporal_hybrid(THD*, my_timespec_t)` to support timespec formatting.
`sql/sql_class.h` / `sql/sql_class.cc`	Adds `THD::timestamp_to_string()` and `TimestampString` helper for warning formatting.
`include/my_time.h`	Introduces `my_timespec_t` plus comparisons/operators and min/max sentinels.
`sql/share/errmsg-utf8.txt`	Renames/adjusts warning text and adds new warnings for STARTS correction and slow history scan.
`sql/field.h` / `sql/field.cc`	Adds `Field_vers_trx_id::get_timestamp()` for TRX_ID-based versioning timestamp lookup.
`sql/event_data_objects.cc`	Clarifies documentation for interval-based time computation.
`mysql-test/suite/versioning/t/partition2.test`	Adds new test coverage for MDEV-25529 scenarios (AUTO, FORCE, STARTS correction, index vs scan, etc.).
`mysql-test/suite/versioning/r/partition2.result`	Expected output for the new `partition2` test.
`mysql-test/suite/versioning/r/partition.result`	Updates expected warning text for STARTS warning message change.
`mysql-test/main/partition.test`	Adds coverage for improved ALTER TABLE FORCE syntax variants.
`mysql-test/main/partition.result`	Expected output for the FORCE syntax additions.

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sql/sql_table.cc

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Pull request overview

This PR improves AUTO system-versioning partition creation during ALTER TABLE by inspecting existing historical row ranges and auto-adjusting partition STARTS/partition counts to cover pre-existing history (with warnings when user STARTS is inconsistent), and expands FORCE syntax ordering for partitioning clauses.

Changes:

Add TABLE::vers_get_history_range() to compute min/max historical ROW END timestamps (prefer index read; fall back to scan with warning).
Adjust AUTO versioning partition creation to derive STARTS/partition count from detected history range, honoring FORCE and explicit partition lists.
Add helpers for timestamp/interval formatting and update tests/expected results for new warnings and grammar.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
sql/table.h	Declares `TABLE::vers_get_history_range()` under partition engine builds.
sql/sql_yacc.yy	Extends ALTER TABLE grammar to accept `partitioning/remove partitioning` before/after alter_list (FORCE syntax order).
sql/sql_type.h	Adds `Temporal_hybrid(THD*, my_timespec_t)` constructor.
sql/sql_type.cc	Implements `Temporal_hybrid` construction from seconds+microseconds.
sql/sql_time.h	Adds `interval2sec()` / `interval2usec()` helpers.
sql/sql_time.cc	Replaces COMBINE macro usage with new interval helpers.
sql/sql_table.cc	Includes `key.h`, renames comparator to `key_eq`, and implements `TABLE::vers_get_history_range()`.
sql/sql_partition.cc	Adds AUTO history-derived partition-count logic and `vers_calc_hist_parts()` helper.
sql/sql_class.h	Adds `THD::timestamp_to_string()` and `TimestampString` helper class.
sql/sql_class.cc	Implements `THD::timestamp_to_string()`.
sql/share/errmsg-utf8.txt	Introduces/renames warnings for STARTS/slow scan and updates message text to include timestamps.
sql/partition_info.h	Tracks whether STARTS was specified (`starts_clause`) and exposes `vers_set_starts()`.
sql/partition_info.cc	Implements `vers_set_starts()` rounding and updates STARTS warning behavior.
sql/field.h	Adds `Field_vers_trx_id::get_timestamp()` override declaration.
sql/field.cc	Implements TRX_ID timestamp lookup for versioning commit timestamps.
sql/event_data_objects.cc	Expands comment describing next-time computation semantics.
mysql-test/suite/versioning/t/partition2.test	Adds coverage for MDEV-25529 AUTO history partitioning, warnings, FORCE behavior, and slow-scan path.
mysql-test/suite/versioning/r/partition2.result	Expected output for the new `partition2.test`.
mysql-test/suite/versioning/r/partition.result	Updates expected STARTS warning text to include timestamps.
mysql-test/main/partition.test	Adds regression coverage for improved FORCE syntax ordering.
mysql-test/main/partition.result	Expected output for updated FORCE syntax test.
include/my_time.h	Introduces `my_timespec_t` plus comparisons and min/max sentinels.

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sql/sql_class.cc

+bool THD::timestamp_to_string(String *str, uint dec, my_timespec_t ts)
+{
+  Temporal_hybrid th(this, ts);
+  return th.to_string(str, dec);


sql/sql_partition.cc

+    }
+
+    start= thd->variables.time_zone->TIME_to_gmt_sec(&boundary, &error);
+    if (start <= 0 || error)


sql/sql_partition.cc

+
+  MYSQL_TIME boundary;
+  thd->variables.time_zone->gmt_sec_to_TIME(&boundary, start);
+


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MDEV-25529 TimestampString for printing timestamps

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MDEV-25529 set_up_default_partitions() ER_OUT_OF_RESOURCES error

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		MYSQL_TIME boundary;
		thd->variables.time_zone->gmt_sec_to_TIME(&boundary, start);

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midenok commented Apr 14, 2026 •

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