Populate HISTORY.md from git history

Reconstructed one entry per real release (0.1.0 through 0.9.7) from each
tag's actual diff, at pgxntool/HISTORY.asc's level of detail - a paragraph or
== per-change section, not just a version bump line. Also credits the one
real fix since 0.9.7 (dropping a redundant, unconditional client_min_messages
override in the install script) under the pending "stable" section.

Author: jnasbyupgrade

HISTORY.md

@@ -3,10 +3,88 @@
 stable
 ------
 
-No user-facing changes yet.
+== Fix client_min_messages handling in the install script
+CREATE EXTENSION already raises client_min_messages to WARNING for the install
+script (only-raising, so a stricter caller is respected) and restores it
+afterward - the extension's own `SET client_min_messages = WARNING` was
+redundant and, being unconditional, could lower a stricter caller's level
+during install. Removed.
+
+0.9.7
+-----
+
+Distribution-only release - the extension version itself stayed at `0.9.6`
+(see RELEASE.md's note on distribution vs. extension versions). Raised the
+minimum supported PostgreSQL version to 9.4 (from 9.3), matching the jsonb
+functions added in 0.9.5, and enabled Travis CI.
+
+0.9.6
+-----
+
+== Fix functions failing when installed outside the search_path
+`null_count()`/`not_null_count()` and their trigger counterparts called each
+other unqualified, so installing count_nulls into a schema not on the
+caller's search_path broke them. All internal calls are now qualified with
+`@extschema@`. Because that qualification is baked into the install script at
+`CREATE EXTENSION` time, count_nulls is no longer relocatable
+(`relocatable = false`).
+
+0.9.5
+-----
+
+== Change null_count()/not_null_count() to return int instead of bigint
+Reverted the anyarray variants' return type from bigint (introduced in 0.1.0)
+back to int - a count of NULL arguments realistically never approaches
+bigint's range.
+
+== Add jsonb support
+Added jsonb overloads of `null_count()`/`not_null_count()`; the existing json
+overloads now delegate to them via a cast instead of duplicating the
+`json_each_text` logic.
+
+0.9.4
+-----
+
+Metadata-only release: PostgreSQL's control-file parser rejects comments
+inside `prereqs`, which the previous release's `META.in.json` had; fixed, and
+documented the PostgreSQL 9.3 requirement.
+
+0.9.3
+-----
+
+Adopted pgxntool (https://github.com/decibel/pgxntool) as the project's build
+system. No functional changes.
+
+0.9.2
+-----
+
+No functional changes - added the first upgrade script (`0.9.0` -> `0.9.2`)
+and adjusted where `make dist` writes its distribution zip.
+
+0.9.1
+-----
+
+== Add null_count_trigger()/not_null_count_trigger()
+Trigger functions for enforcing "this row must have exactly N NULL (or NOT
+NULL) columns" as a table constraint, usable via
+`CREATE TRIGGER ... EXECUTE PROCEDURE null_count_trigger(N)`.
+
+0.9.0
+-----
+
+== Add json support
+Added `null_count(json)`/`not_null_count(json)`, counting NULL values across
+a JSON object's top-level keys.
+
+0.1.0
+-----
+
+Initial release. `null_count()`/`not_null_count()` variadic functions,
+counting NULL (or NOT NULL) arguments passed to them.
 
 ---
 
-Releases before this file existed (`0.1.0` through `0.9.7`) aren't detailed here;
-see https://pgxn.org/dist/count_nulls/ and the corresponding git tags for what
-shipped in each.
+Every entry above from `0.1.0` through `0.9.7` was reconstructed from git
+history when this file was created (2026-07-24), not written contemporaneously
+with each release - see the corresponding git tags and
+https://pgxn.org/dist/count_nulls/ for the authoritative record.