1 files changed, 74 insertions, 0 deletions
diff --git a/pgruntime/helpers.go b/pgruntime/helpers.go
new file mode 100644
index 0000000..1019e6e
--- /dev/null
+++ b/pgruntime/helpers.go
@@ -0,0 +1,74 @@
+// SPDX-FileCopyrightText: 2026 Stefan Majewsky <majewsky@gmx.net>
+// SPDX-License-Identifier: Apache-2.0
+
+package pgruntime
+
+import (
+	"context"
+	"database/sql"
+	"strings"
+
+	"go.xyrillian.de/gg/errext"
+	"go.xyrillian.de/gg/gsql"
+)
+
+// Convenience function for executing a one-off SQL query returning no rows.
+// TODO: move to gsql
+func execQuery(ctx context.Context, db gsql.Handle, query string, args []any) (sql.Result, error) {
+	stmt, err := db.GSQLPrepare(ctx, query, false)
+	if err != nil {
+		return nil, err
+	}
+	result, err := stmt.Exec(ctx, args)
+	return result, errext.WithCleanup(err, "stmt.Close", stmt.Close())
+}
+
+// Convenience function for executing a one-off SQL query returning one row.
+func queryRow(ctx context.Context, db gsql.Handle, query string, args, slots []any) error {
+	stmt, err := db.GSQLPrepare(ctx, query, false)
+	if err != nil {
+		return err
+	}
+	err = stmt.QueryRow(ctx, args, slots)
+	return errext.WithCleanup(err, "stmt.Close", stmt.Close())
+}
+
+// Convenience function for executing a one-off SQL query returning one value.
+// TODO: move to gsql
+func selectOneValue[T any](ctx context.Context, db gsql.Handle, query string, args ...any) (T, error) {
+	stmt, err := db.GSQLPrepare(ctx, query, false)
+	if err != nil {
+		var none T
+		return none, err
+	}
+
+	var result T
+	err = stmt.QueryRow(ctx, args, []any{&result})
+	return result, errext.WithCleanup(err, "stmt.Close", stmt.Close())
+}
+
+// Convenience function for executing a one-off SQL query returning several single-column rows.
+// TODO: move to gsql (and also add ForeachValue with a callback instead of a slice return, maybe even ForeachPair and ForeachTriple)
+func selectSeveralValues[T any](ctx context.Context, db gsql.Handle, query string, args ...any) ([]T, error) {
+	rows, err := db.GSQLQuery(ctx, query, args)
+	if err != nil {
+		return nil, err
+	}
+	var result []T
+	for rows.Next() {
+		// TODO: this should share growRecordSlice() from Oblast to optimize allocations
+		var value T
+		err := rows.Scan(&value)
+		if err != nil {
+			return nil, errext.WithCleanup(err, "rows.Close", rows.Close())
+		}
+		result = append(result, value)
+	}
+	return result, errext.WithCleanup(nil, "rows.Err", rows.Err())
+}
+
+// Convenience function for preparing an identifier that needs to be inserted into a query verbatim
+// (e.g. a database name for CREATE DATABASE).
+func quoteIdentifier(name string) string {
+	return `"` + strings.ReplaceAll(name, `"`, `""`) + `"`
+}