github.com/jackc/pgx/v5 v5.10.0: Queue queries and inspect batch operations using pgx.Batch

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: Queue queries and inspect batch operations using pgx.Batch
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/jackc/pgx/v5@v5.10.0
Demonstrate these symbols/APIs:
  - pgx.Batch
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@11.8.0
  - runtime: node@24.13.1

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:cdf45e0fa662fbcc70d63230a518dad968a2c9763f306cab8bd78421e70cf375","contract":["pgx.Batch initializes with empty QueuedQueries and zero length","pgx.Batch.Queue appends query string and positional arguments to QueuedQueries","pgx.Batch.Queue preserves execution order across multiple queued queries","pgx.Batch.Len returns the total number of queued queries","pgx.QueuedQuery.Exec registers command execution callback","pgx.QueuedQuery.Query registers rows query callback","pgx.QueuedQuery.QueryRow registers single row query callback"],"goal":"Queue queries and inspect batch operations using pgx.Batch","kind":"HOW","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["pgx.Batch"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","ecosystem":"golang","os":"windows","osVersionBucket":"11","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["pgx.Batch"],"verifierAdapter":"golang@1"}

module sample

go 1.26.5

require (
	github.com/jackc/pgpassfile v1.0.0 // indirect
	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
	github.com/jackc/pgx/v5 v5.10.0 // indirect
	golang.org/x/text v0.29.0 // indirect
)

github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761/go.mod h1:5TJZWKEWniPve33vlWYSoGYefn3gLQRzjfDlhSJ9ZKM=
github.com/jackc/pgx/v5 v5.10.0 h1:VhSvgU2jSli8o3AqIEOTJr7rZwAEUVo4E4XhR94Zfr0=
github.com/jackc/pgx/v5 v5.10.0/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package main

import (
	"fmt"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

func main() {
	batch := &pgx.Batch{}

	// Queue an INSERT query with positional arguments
	q1 := batch.Queue(
		"INSERT INTO users (id, name, active) VALUES ($1, $2, $3)",
		1, "Alice", true,
	)
	q1.Exec(func(ct pgconn.CommandTag) error {
		fmt.Printf("Inserted rows: %d\n", ct.RowsAffected())
		return nil
	})

	// Queue a SELECT query with arguments
	q2 := batch.Queue(
		"SELECT id, name FROM users WHERE id = $1",
		1,
	)
	q2.QueryRow(func(row pgx.Row) error {
		var id int
		var name string
		if err := row.Scan(&id, &name); err != nil {
			return err
		}
		fmt.Printf("User: %d, %s\n", id, name)
		return nil
	})

	// Queue a count query
	batch.Queue("SELECT count(*) FROM users")

	fmt.Printf("Total queued queries: %d\n", batch.Len())
	for i, q := range batch.QueuedQueries {
		fmt.Printf("Query %d: %s (args: %v)\n", i+1, q.SQL, q.Arguments)
	}
}

{
  "schemaVersion": 1,
  "goal": "Queue queries and inspect batch operations using pgx.Batch",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/jackc/pgx/v5@v5.10.0"
  ],
  "symbols": [
    "pgx.Batch"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@11.8.0",
    "runtime": "node@24.13.1"
  }
}

package main

import (
	"fmt"
	"os"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

func main() {
	// Assertion 1: pgx.Batch initializes with empty QueuedQueries and zero length
	batch := &pgx.Batch{}
	if batch.Len() != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected initial Len() to be 0, got %d\n", batch.Len())
		os.Exit(1)
	}
	if len(batch.QueuedQueries) != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected initial QueuedQueries to be empty, got len %d\n", len(batch.QueuedQueries))
		os.Exit(1)
	}

	// Assertion 2: pgx.Batch.Queue appends query string and positional arguments to QueuedQueries
	q1 := batch.Queue(
		"INSERT INTO users (id, name, active) VALUES ($1, $2, $3)",
		101, "Alice", true,
	)
	if q1 == nil {
		fmt.Fprintf(os.Stderr, "FAIL: Queue returned nil QueuedQuery\n")
		os.Exit(1)
	}
	if batch.Len() != 1 {
		fmt.Fprintf(os.Stderr, "FAIL: expected Len() == 1 after first queue, got %d\n", batch.Len())
		os.Exit(1)
	}
	if batch.QueuedQueries[0].SQL != "INSERT INTO users (id, name, active) VALUES ($1, $2, $3)" {
		fmt.Fprintf(os.Stderr, "FAIL: SQL mismatch, got %s\n", batch.QueuedQueries[0].SQL)
		os.Exit(1)
	}
	if len(batch.QueuedQueries[0].Arguments) != 3 ||
		batch.QueuedQueries[0].Arguments[0] != 101 ||
		batch.QueuedQueries[0].Arguments[1] != "Alice" ||
		batch.QueuedQueries[0].Arguments[2] != true {
		fmt.Fprintf(os.Stderr, "FAIL: Arguments mismatch, got %v\n", batch.QueuedQueries[0].Arguments)
		os.Exit(1)
	}

	// Assertion 3: pgx.Batch.Queue preserves execution order across multiple queued queries
	q2 := batch.Queue("SELECT id, name FROM users WHERE id = $1", 101)
	q3 := batch.Queue("SELECT count(*) FROM users")
	if batch.QueuedQueries[1] != q2 || batch.QueuedQueries[2] != q3 {
		fmt.Fprintf(os.Stderr, "FAIL: QueuedQueries order or references mismatch\n")
		os.Exit(1)
	}
	if batch.QueuedQueries[1].SQL != "SELECT id, name FROM users WHERE id = $1" ||
		batch.QueuedQueries[2].SQL != "SELECT count(*) FROM users" {
		fmt.Fprintf(os.Stderr, "FAIL: SQL queries ordering mismatch\n")
		os.Exit(1)
	}

	// Assertion 4: pgx.Batch.Len returns the total number of queued queries
	if batch.Len() != 3 {
		fmt.Fprintf(os.Stderr, "FAIL: expected Len() == 3, got %d\n", batch.Len())
		os.Exit(1)
	}

	// Assertion 5: pgx.QueuedQuery.Exec registers command execution callback
	q1.Exec(func(ct pgconn.CommandTag) error {
		return nil
	})
	if q1.Fn == nil {
		fmt.Fprintf(os.Stderr, "FAIL: Exec did not set internal handler function\n")
		os.Exit(1)
	}

	// Assertion 6: pgx.QueuedQuery.Query registers rows query callback
	q2.Query(func(rows pgx.Rows) error {
		return nil
	})
	if q2.Fn == nil {
		fmt.Fprintf(os.Stderr, "FAIL: Query did not set internal handler function\n")
		os.Exit(1)
	}

	// Assertion 7: pgx.QueuedQuery.QueryRow registers single row query callback
	q3.QueryRow(func(row pgx.Row) error {
		return nil
	})
	if q3.Fn == nil {
		fmt.Fprintf(os.Stderr, "FAIL: QueryRow did not set internal handler function\n")
		os.Exit(1)
	}

	fmt.Println("PASS: all contract assertions passed for pkg:golang/github.com/jackc/pgx/v5@v5.10.0")
}