// fetchEntries is the shared implementation for GetEntries and GetEntriesWithCount.
// When withCount is true, count(*) OVER() is included in the SELECT and the total
// count of matching rows is returned; otherwise the returned count is 0.
func (e *EntryQueryBuilder) fetchEntries(withCount bool) (model.Entries, int, error) {
	countColumn := ""
	if withCount {
		countColumn = "count(*) OVER(),"
	}

	query := `
		SELECT
			` + countColumn + `
			e.id,
			e.user_id,
…
			entries e
		INNER JOIN
			feeds f ON f.id=e.feed_id
		INNER JOIN
			categories c ON c.id=f.category_id
		LEFT JOIN
			feed_icons fi ON fi.feed_id=f.id
		LEFT JOIN
			icons i ON i.id=fi.icon_id
		INNER JOIN
			users u ON u.id=e.user_id
		WHERE ` + e.buildCondition() + " " + e.buildSorting()

	rows, err := e.store.db.Query(query, e.args...)
…
func (e *EntryQueryBuilder) buildCondition() string {
	return strings.Join(e.conditions, " AND ")
}

func (e *EntryQueryBuilder) buildSorting() string {
	var parts string

	if len(e.sortExpressions) > 0 {
		parts += " ORDER BY " + strings.Join(e.sortExpressions, ", ")
	}

	if e.limit > 0 {
		parts += " LIMIT " + strconv.Itoa(e.limit)
	}

	if e.offset > 0 {
		parts += " OFFSET " + strconv.Itoa(e.offset)
	}

	return parts
…
// NewEntryQueryBuilder returns a new EntryQueryBuilder.
func (s *Storage) NewEntryQueryBuilder(userID int64) *EntryQueryBuilder {
	return &EntryQueryBuilder{
		store:      s,
		args:       []any{userID},
		conditions: []string{"e.user_id = $1"},
	}
}

Warm-up