Remove QueryArgs

An external SQL builder like github.com/jackc/pgsql should be used
instead.

bench_test.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"strconv"
 	"strings"
 	"testing"
 	"time"
@@ -504,6 +505,13 @@ func benchmarkWriteNRowsViaInsert(b *testing.B, n int) {
 	}
 }
 
+type queryArgs []interface{}
+
+func (qa *queryArgs) Append(v interface{}) string {
+	*qa = append(*qa, v)
+	return "$" + strconv.Itoa(len(*qa))
+}
+
 // note this function is only used for benchmarks -- it doesn't escape tableName
 // or columnNames
 func multiInsert(conn *pgx.Conn, tableName string, columnNames []string, rowSrc pgx.CopyFromSource) (int, error) {
@@ -512,7 +520,7 @@ func multiInsert(conn *pgx.Conn, tableName string, columnNames []string, rowSrc
 	rowCount := 0
 
 	sqlBuf := &bytes.Buffer{}
-	args := make(pgx.QueryArgs, 0)
+	args := make(queryArgs, 0)
 
 	resetQuery := func() {
 		sqlBuf.Reset()

sql.go

@@ -1,29 +0,0 @@
-package pgx
-
-import (
-	"strconv"
-)
-
-// QueryArgs is a container for arguments to an SQL query. It is helpful when
-// building SQL statements where the number of arguments is variable.
-type QueryArgs []interface{}
-
-var placeholders []string
-
-func init() {
-	placeholders = make([]string, 64)
-
-	for i := 1; i < 64; i++ {
-		placeholders[i] = "$" + strconv.Itoa(i)
-	}
-}
-
-// Append adds a value to qa and returns the placeholder value for the
-// argument. e.g. $1, $2, etc.
-func (qa *QueryArgs) Append(v interface{}) string {
-	*qa = append(*qa, v)
-	if len(*qa) < len(placeholders) {
-		return placeholders[len(*qa)]
-	}
-	return "$" + strconv.Itoa(len(*qa))
-}

sql_test.go

@@ -1,36 +0,0 @@
-package pgx_test
-
-import (
-	"strconv"
-	"testing"
-
-	"github.com/jackc/pgx/v4"
-)
-
-func TestQueryArgs(t *testing.T) {
-	var qa pgx.QueryArgs
-
-	for i := 1; i < 512; i++ {
-		expectedPlaceholder := "$" + strconv.Itoa(i)
-		placeholder := qa.Append(i)
-		if placeholder != expectedPlaceholder {
-			t.Errorf(`Expected qa.Append to return "%s", but it returned "%s"`, expectedPlaceholder, placeholder)
-		}
-	}
-}
-
-func BenchmarkQueryArgs(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		qa := pgx.QueryArgs(make([]interface{}, 0, 16))
-		qa.Append("foo1")
-		qa.Append("foo2")
-		qa.Append("foo3")
-		qa.Append("foo4")
-		qa.Append("foo5")
-		qa.Append("foo6")
-		qa.Append("foo7")
-		qa.Append("foo8")
-		qa.Append("foo9")
-		qa.Append("foo10")
-	}
-}