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Update lab_9.sql #29

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Update lab_9.sql #29

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15 changes: 5 additions & 10 deletions lab_9.sql
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Original file line number Diff line number Diff line change
Expand Up @@ -377,7 +377,7 @@ rollback to sp_before_update;
--6)
update schema1.employees
set department_id = 10
where employee_id = 14;
where employee_id = 5;

-- Корректное обновление одного сотрудника.

Expand Down Expand Up @@ -417,7 +417,7 @@ begin;
--3)изменить email первого сотрудника

update schema1.employees
set email = email || session1@yandex.ru
set email = email || 's1'
where employee_id = 1;

-- Изменение выполнено, но не видно в других сессиях.
Expand Down Expand Up @@ -453,7 +453,7 @@ where employee_id = 1;
--9) изменить email того же сотрудника

update schema1.employees
set email = email || ',session2@yandex.ru'
set email = email || 's2'
where employee_id = 1;

-- Изменение успешно.
Expand Down Expand Up @@ -577,7 +577,7 @@ begin;
--3) изменить email первого сотрудника

update schema1.employees
set email = email || ',session1@yandex.ru'
set email = email || 's1'
where employee_id = 1;

-- первое обращение к таблице зафиксировало snapshot.
Expand Down Expand Up @@ -619,7 +619,7 @@ where employee_id = 1;
--9) изменить email того же сотрудника

update schema1.employees
set email = email || ',session2@yandex.ru'
set email = email || 's2'
where employee_id = 1;

-- UPDATE будет ждать освобождения блокировки строки Session 1.
Expand Down Expand Up @@ -725,8 +725,3 @@ commit;
-- После commit snapshot “сбрасывается”.
-- В следующей новой транзакции select уже увидит новый телефон,
-- зафиксированный второй сессией.