}

		builder.WriteQuoted(column)
	}

	if len(groupBy.Having) > 0 {
		builder.WriteString(" HAVING ")
		Where{Exprs: groupBy.Having}.Build(builder)
	}
}

// MergeClause merge group by clause
func (groupBy GroupBy) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(GroupBy); ok {
		copiedColumns := make([]Column, len(v.Columns))
		copy(copiedColumns, v.Columns)

			if idx > 0 {
				builder.WriteByte(',')
			}

			builder.WriteQuoted(column)
		}
	} else {
		builder.WriteByte('*')
	}
}

// MergeClause merge order by clauses
func (returning Returning) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Returning); ok {
		returning.Columns = append(v.Columns, returning.Columns...)
	}

	clause.Expression = returning

		if limit.Limit != nil && *limit.Limit >= 0 {
			builder.WriteByte(' ')
		}
		builder.WriteString("OFFSET ")
		builder.AddVar(builder, limit.Offset)
	}
}

// MergeClause merge order by clauses
func (limit Limit) MergeClause(clause *Clause) {
	clause.Name = ""

	if v, ok := clause.Expression.(Limit); ok {
		if (limit.Limit == nil || *limit.Limit == 0) && v.Limit != nil {
			limit.Limit = v.Limit
		}

		builder.WriteString(" OF ")
		builder.WriteQuoted(locking.Table)
	}

	if locking.Options != "" {
		builder.WriteByte(' ')
		builder.WriteString(locking.Options)
	}
}

// MergeClause merge order by clauses
func (locking Locking) MergeClause(clause *Clause) {
	clause.Expression = locking

	}

	if len(onConflict.Where.Exprs) > 0 {
		builder.WriteString(" WHERE ")
		onConflict.Where.Build(builder)
		builder.WriteByte(' ')
	}
}

// MergeClause merge onConflict clauses
func (onConflict OnConflict) MergeClause(clause *Clause) {
	clause.Expression = onConflict

	}

	builder.WriteString("INTO ")
	if insert.Table.Name == "" {
		builder.WriteQuoted(currentTable)
	} else {
		builder.WriteQuoted(insert.Table)
	}
}

// MergeClause merge insert clause
func (insert Insert) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Insert); ok {
		if insert.Modifier == "" {
			insert.Modifier = v.Modifier
		}
		if insert.Table.Name == "" {
			insert.Table = v.Table

		}
	} else {
		builder.WriteQuoted(currentTable)
	}

	for _, join := range from.Joins {
		builder.WriteByte(' ')
		join.Build(builder)
	}
}

// MergeClause merge from clause
func (from From) MergeClause(clause *Clause) {
	clause.Expression = from

			if idx > 0 {
				builder.WriteByte(',')
			}

			builder.WriteQuoted(column.Column)
			if column.Desc {
				builder.WriteString(" DESC")
			}
		}
	}
}

// MergeClause merge order by clauses
func (orderBy OrderBy) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(OrderBy); ok {
		for i := len(orderBy.Columns) - 1; i >= 0; i-- {
			if orderBy.Columns[i].Reorder {
				orderBy.Columns = orderBy.Columns[i:]

		builder.WriteByte(' ')
	}

	if update.Table.Name == "" {
		builder.WriteQuoted(currentTable)
	} else {
		builder.WriteQuoted(update.Table)
	}
}

// MergeClause merge update clause
func (update Update) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Update); ok {
		if update.Modifier == "" {
			update.Modifier = v.Modifier
		}
		if update.Table.Name == "" {
			update.Table = v.Table

			}

			builder.WriteByte('(')
			builder.AddVar(builder, value...)
			builder.WriteByte(')')
		}
	} else {
		builder.WriteString("DEFAULT VALUES")
	}
}

// MergeClause merge values clauses
func (values Values) MergeClause(clause *Clause) {
	clause.Name = ""
	clause.Expression = values