SQL
select 
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00'))      - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00'))      - 7 * id day), '')
	as Mon,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 1  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 1  - 7 * id day), '')
    as Tue,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 2  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 2  - 7 * id day), '')
    as Wed,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 3  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 3  - 7 * id day), '')
    as Thu,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 4  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 4  - 7 * id day), '')
    as Fri,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 5  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 5  - 7 * id day), '')
    as Sat,
	if (month(now()) = month(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 6  - 7 * id day), dayofmonth(concat(year(now()), '-', month(now()), '-01 00:00:00') - INTERVAL weekday(concat(year(now()), '-', month(now()), '-01 00:00:00')) - 6  - 7 * id day), '')
    as Sun from tbl; 
В tbl:
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