fix: column field singularization, duplicate parameter names, sequence args typing

.changes/unreleased/Fixed-duplicate-params.yaml

@@ -0,0 +1,6 @@
+kind: Fixed
+body: Queries mixing a positional reference with a same-named sqlc.arg() no longer generate a duplicate function parameter
+time: 2026-06-09T00:00:01.0000000Z
+custom:
+    Author: Mic92
+    PR: "164"

.changes/unreleased/Fixed-field-singularization.yaml

@@ -0,0 +1,6 @@
+kind: Fixed
+body: Column field names are no longer singularized (`outputs` generated an `output` field); duplicate selected columns get suffixed fields instead of an invalid class
+time: 2026-06-09T00:00:00.0000000Z
+custom:
+    Author: Mic92
+    PR: "164"

.changes/unreleased/Fixed-queryresults-sequence.yaml

@@ -0,0 +1,6 @@
+kind: Fixed
+body: QueryResultsArgsType includes Sequence so array parameters of :many queries type-check
+time: 2026-06-09T00:00:02.0000000Z
+custom:
+    Author: Mic92
+    PR: "164"

internal/builders.go

@@ -261,9 +261,19 @@ func (gen *PythonGenerator) buildQueries(tables []core.Table) ([]core.Query, err
 				}}
 			} else if len(query.Params) >= 1 {
 				var values []core.QueryValue
+				// Positional ($n) and named (sqlc.arg) references
+				// can infer the same name; suffix duplicates to keep
+				// the function definition valid.
+				seenParams := map[string]int{}
 				for _, p := range query.Params {
+					baseName := core.Escape(core.ParamName(p))
+					name := baseName
+					if n := seenParams[baseName]; n > 0 {
+						name = fmt.Sprintf("%s_%d", baseName, n+1)
+					}
+					seenParams[baseName]++
 					values = append(values, core.QueryValue{
-						Name:   core.Escape(core.ParamName(p)),
+						Name:   name,
 						DBName: p.Column.GetName(),
 						Typ:    gen.makePythonType(p.Column),
 						Column: p.Column,
@@ -370,11 +380,23 @@ func (gen *PythonGenerator) columnsToStruct(name string, columns []goColumn, use
 			fieldName = fmt.Sprintf("%s_%d", fieldName, suffix)
 		}
 
-		f := core.Column{
-			Name: inflection.Singular(inflection.SingularParams{
-				Name:       core.ColumnName(c.Column, i),
+		// Singularizing belongs to table names only; on columns it
+		// renames e.g. "outputs" to "output". Embedded fields are
+		// singularized: they hold one row of the joined table.
+		// Duplicate columns need the suffix in the field name,
+		// otherwise the class ends up with duplicate fields.
+		pyFieldName := core.ColumnName(c.Column, i)
+		if c.embed != nil {
+			pyFieldName = inflection.Singular(inflection.SingularParams{
+				Name:       pyFieldName,
 				Exclusions: gen.config.InflectionExcludeTableNames,
-			}),
+			})
+		}
+		if suffix > 0 {
+			pyFieldName = fmt.Sprintf("%s_%d", pyFieldName, suffix)
+		}
+		f := core.Column{
+			Name:   pyFieldName,
 			DBName: colName,
 			Column: c.Column,
 		}

internal/core/importer.go

@@ -325,7 +325,9 @@ func (i *Importer) queryImports(fileName string) ([]string, []string, []string)
 		if IsInMultipleMaps("datetime", std, typeCheck) {
 			queryResultsArgsType += " | datetime.date | datetime.time | datetime.datetime | datetime.timedelta"
 		}
-		queryResultsArgsType += " | None"
+		// asyncpg passes array-typed parameters (e.g. text[]) as
+		// sequences.
+		queryResultsArgsType += " | collections.abc.Sequence[typing.Any] | None"
 		typeLines = append(typeLines, queryResultsArgsType)
 	}
 

test/driver_aiosqlite/attrs/classes/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/attrs/classes/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/attrs/classes/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -22,7 +22,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.attrs.classes import models
 

test/driver_aiosqlite/attrs/functions/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/attrs/functions/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/attrs/functions/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -59,7 +59,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.attrs.functions import models
 

test/driver_aiosqlite/dataclass/classes/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/dataclass/classes/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/dataclass/classes/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -21,7 +21,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.dataclass.classes import models
 

test/driver_aiosqlite/dataclass/functions/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/dataclass/functions/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/dataclass/functions/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -59,7 +59,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.dataclass.functions import models
 

test/driver_aiosqlite/msgspec/classes/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/msgspec/classes/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/msgspec/classes/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -21,7 +21,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.msgspec.classes import models
 

test/driver_aiosqlite/msgspec/functions/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_aiosqlite/msgspec/functions/models.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 

test/driver_aiosqlite/msgspec/functions/queries.py

@@ -1,7 +1,7 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing queries from file queries.sql."""
 from __future__ import annotations
 
@@ -59,7 +59,7 @@
     import collections.abc
     import sqlite3
 
-    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | None
+    QueryResultsArgsType: typing.TypeAlias = int | float | str | memoryview | decimal.Decimal | datetime.date | datetime.time | datetime.datetime | datetime.timedelta | collections.abc.Sequence[typing.Any] | None
 
 from test.driver_aiosqlite.msgspec.functions import models
 

test/driver_aiosqlite/sqlc.yaml

@@ -3,7 +3,7 @@ plugins:
   - name: python
     wasm:
       url: file://sqlc-gen-better-python.wasm
-      sha256: ee7bd0c07b784b80ea8c5853d9a6a04c51a7abbfd2663f470e9a5d2f623b967e
+      sha256: 53c4de16a585391d2ff2a545b12d04bce82b6e194873042706d471d343f2bbc2
 sql:
   - schema: schema.sql
     queries: queries.sql

test/driver_asyncpg/attrs/classes/__init__.py

@@ -1,5 +1,5 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Package containing queries and models automatically generated using sqlc-gen-better-python."""

test/driver_asyncpg/attrs/classes/models.py

@@ -1,11 +1,12 @@
 # Code generated by sqlc. DO NOT EDIT.
 # versions:
-#   sqlc v1.30.0
-#   sqlc-gen-better-python v0.4.4
+#   sqlc v1.31.1
+#   sqlc-gen-better-python v0.4.5
 """Module containing models."""
 from __future__ import annotations
 
 __all__: collections.abc.Sequence[str] = (
+    "TestFieldNaming",
     "TestInnerPostgresType",
     "TestPostgresType",
     "TestTypeOverride",
@@ -22,6 +23,23 @@
     import uuid
 
 
+@attrs.define()
+class TestFieldNaming:
+    """Model representing TestFieldNaming.
+
+    Attributes
+    ----------
+    id : int
+    outputs : str
+    groups : collections.abc.Sequence[str]
+
+    """
+
+    id: int
+    outputs: str
+    groups: collections.abc.Sequence[str]
+
+
 @attrs.define()
 class TestInnerPostgresType:
     """Model representing TestInnerPostgresType.