N. Ramirez escribió:
> I do not have an operation as it must be when use the functions to do
> 2-phase commit
>
> Example create table prueba (a int, b int);
> begin;
> PREPARE TRANSACTION 'aaaa';
> insert into prueba values (1,2);
> ROLLBACK PREPARED 'aaaa'; select * from prueba
> a b
> -----------------------------
> 1 2
> because?
> it did not do rollback?
> as it is used the method of 2-phase commit?
It did rollback, but you put the insert outside the prepared
transaction, so it was committed independently. Try this:
alvherre=# create table prueba (a int, b int);
CREATE TABLE
alvherre=# begin;
BEGIN
alvherre=# insert into prueba values (1, 2);
INSERT 0 1
alvherre=# prepare transaction 'aaaa';
PREPARE TRANSACTION
alvherre=# select * from prueba;
a | b
---+---
(0 filas)
alvherre=# rollback prepared 'aaaa';
ROLLBACK PREPARED
alvherre=# select * from prueba;
a | b
---+---
(0 filas)
alvherre=# begin;
BEGIN
alvherre=# insert into prueba values (1, 2);
INSERT 0 1
alvherre=# prepare transaction 'bbb';
PREPARE TRANSACTION
alvherre=# select * from prueba;
a | b
---+---
(0 filas)
alvherre=# commit prepared 'bbb';
COMMIT PREPARED
alvherre=# select * from prueba;
a | b
---+---
1 | 2
(1 fila)
> idem for use of dblink
Not sure what you mean here.
--
Alvaro Herrera http://www.CommandPrompt.com/
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