new api

.formatter.exs

@@ -1,5 +1,5 @@
 # Used by "mix format"
 [
-  inputs: ["{mix,.formatter}.exs", "{config,lib,test,bench}/**/*.{ex,exs}"],
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test,bench,dev}/**/*.{ex,exs}"],
   import_deps: [:stream_data]
 ]

.github/workflows/bench.yml

@@ -2,7 +2,6 @@ name: bench
 
 on:
   workflow_dispatch:
-  pull_request:
   push:
     branches: [master]
   schedule:

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ on:
 
 jobs:
   test:
-    name: "test @ elixir:${{ matrix.elixir }} otp:${{ matrix.otp }} clickhouse:${{ matrix.clickhouse || 'latest' }} tz:${{ matrix.timezone || 'utc' }}${{ matrix.dialyzer && ' +dialyzer' || '' }}${{ matrix.lint && ' +lint' || '' }}"
+    name: "test @ elixir:${{ matrix.elixir }} otp:${{ matrix.otp }} clickhouse:${{ matrix.clickhouse }} ${{ matrix.dialyzer && ' +dialyzer' || '' }}${{ matrix.lint && ' +lint' || '' }}"
     runs-on: ubuntu-latest
 
     env:
@@ -19,42 +19,26 @@ jobs:
     strategy:
       matrix:
         include:
-          # some old elixir/erlang version
-          - elixir: 1.15
-            otp: 25
-
-          # some recent version and non-UTC timezone
-          - elixir: 1.18
-            otp: 27
-            timezone: Europe/Berlin
-
-          # the latest elixir/erlang version with all static checks
-          - elixir: 1.19
-            otp: 28
+          # some old elixir/clickhouse version with the minimum supported OTP
+          # see https://hexdocs.pm/elixir/compatibility-and-deprecations.html#between-elixir-and-erlang-otp
+          - elixir: "1.18"
+            otp: "28"
+            clickhouse: "24.5.4.49"
+
+          # the latest versions with all static checks
+          - elixir: ">0"
+            otp: ">0"
+            clickhouse: "latest"
             dialyzer: true
             lint: true
             coverage: true
 
-          # Plausible versions
-          # - https://github.com/plausible/analytics/blob/master/.tool-versions
-          # - https://github.com/plausible/analytics/blob/master/.github/workflows/elixir.yml
-          - elixir: 1.19.4
-            otp: 27.3.4.6
-            clickhouse: 25.11.5.8
-
-          # some older pre-JSON ClickHouse version
-          # https://github.com/plausible/ch/issues/273
-          - elixir: 1.18
-            otp: 28
-            clickhouse: 24.5.4.49
-
     services:
       clickhouse:
-        image: clickhouse/clickhouse-server:${{ matrix.clickhouse || 'latest' }}
+        image: clickhouse/clickhouse-server:${{ matrix.clickhouse }}
         ports:
           - 8123:8123
         env:
-          TZ: ${{ matrix.timezone || 'UTC' }}
           # https://github.com/ClickHouse/ClickHouse/issues/75494
           CLICKHOUSE_SKIP_USER_SETUP: 1
           options: >-
@@ -110,9 +94,9 @@ jobs:
         uses: actions/cache@v5
         with:
           path: plts
-          key: plts-${{ steps.beam.outputs.elixir-version }}-${{ steps.beam.outputs.otp-version }}-${{ github.head_ref || github.ref }}
+          key: plts-${{ steps.beam.outputs.elixir-version }}-${{ github.head_ref || github.ref }}
           restore-keys: |
-            plts-${{ steps.beam.outputs.elixir-version }}-${{ steps.beam.outputs.otp-version }}-refs/heads/master
+            plts-${{ steps.beam.outputs.elixir-version }}-refs/heads/master
 
       - run: mix dialyzer --format github
         if: ${{ matrix.dialyzer }}

CHANGELOG.md

@@ -1,5 +1,22 @@
 # Changelog
 
+## Unreleased
+
+- **Breaking:** replace DBConnection with NimblePool.
+- **Breaking:** require Elixir 1.18 or later for the built-in `JSON` module and Erlang/OTP 28 or later for `:zstd`.
+- **Breaking:** `Ch.start_link/1` no longer accepts DBConnection options or connection-level ClickHouse options such as `:database`, `:username`, `:password`, `:settings`, `:timeout`, `:scheme`, `:hostname`, `:port`, and `:transport_opts`. Use `:url` for the endpoint, pass ClickHouse settings per query with `Ch.query/4`'s `:settings` option, and pass ClickHouse/database/auth headers per query with `:headers`.
+- **Breaking:** remove DBConnection compatibility APIs and structs such as `Ch.stream/4`, `Ch.run/3`, `Ch.Query`, `Ch.Stream`, DBConnection transactions/checkouts, and DBConnection streaming/collectable inserts.
+- **Breaking:** `Ch.query/4` only accepts named query parameters as a map. Positional and pseudo-positional params such as `[value]` with `{$0:Type}` are no longer supported.
+- **Breaking:** remove query command detection and the `:command` query option.
+- **Breaking:** remove query options `:format`, `:types`, `:encode`, `:decode`, and `:multipart`. Use an `x-clickhouse-format` header or explicit `FORMAT ...` SQL for formats, and pass already-encoded request bodies for inserts.
+- **Breaking:** remove automatic RowBinary insert encoding from `Ch.query/4`. Call `Ch.RowBinary.encode_rows/2` or `Ch.RowBinary.encode_names_and_types/2` explicitly and pass the resulting iodata in the query body.
+- **Breaking:** remove multipart query parameter requests for now. `multipart: true` is no longer supported; see https://github.com/plausible/ch/issues/344 for restoring it.
+- **Breaking:** `Ch.query/4` now returns `%Ch.Result{names: names, rows: rows, headers: headers, data: data}` for successful responses. Decoded `RowBinaryWithNamesAndTypes` responses populate `:names` and `:rows`; raw formats, inserts, DDL, and other empty responses keep the response body in `:data` and leave `:names` and `:rows` as `nil`.
+- **Breaking:** successful inserts, DDL, and other empty responses no longer return `%Ch.Result{command: command, num_rows: num_rows}`. `x-clickhouse-summary` written-row counts are no longer surfaced.
+- **Breaking:** `Ch.RowBinary` no longer has a separate `:binary` type. Use `:string` for ClickHouse `String`; it now preserves raw bytes and no longer replaces invalid UTF-8 with the replacement character.
+- Remove the `Jason` dependency. JSON encoding/decoding now uses Elixir's built-in `JSON` module.
+- Add explicit request and response compression support through HTTP headers. `zstd` and `gzip` response bodies are decompressed automatically for decoded `RowBinaryWithNamesAndTypes` and error responses; raw successful responses are kept as received in `Ch.Result.data`.
+
 ## 0.8.3 (2026-05-12)
 
 - use DBConnection v2.10 https://github.com/plausible/ch/pull/339