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author | Thomas G. Lockhart | 1999-08-08 15:21:50 +0000 |
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committer | Thomas G. Lockhart | 1999-08-08 15:21:50 +0000 |
commit | a76ad509fef621719abb95fedb526e9a0092a312 (patch) | |
tree | 1a5295dbdce9296f23f252898aea402f411e7d23 /src/man/begin.l | |
parent | d0a1919852b8c98f43f2795c23690024707fc1e5 (diff) |
Remove old man pages. All info is in new man pages or other docs.
Diffstat (limited to 'src/man/begin.l')
-rw-r--r-- | src/man/begin.l | 44 |
1 files changed, 0 insertions, 44 deletions
diff --git a/src/man/begin.l b/src/man/begin.l deleted file mode 100644 index 32b9f7cd970..00000000000 --- a/src/man/begin.l +++ /dev/null @@ -1,44 +0,0 @@ -.\" This is -*-nroff-*- -.\" XXX standard disclaimer belongs here.... -.\" $Header: /cvsroot/pgsql/src/man/Attic/begin.l,v 1.6 1999/06/11 05:40:18 vadim Exp $ -.TH BEGIN SQL 11/05/95 PostgreSQL PostgreSQL -.SH NAME -begin - begins a transaction in chained mode -.SH SYNOPSIS -.nf -\fBbegin\fP \fB[transaction|work]\fR -.fi -.SH DESCRIPTION - -By default, Postgres executes transactions in unchained mode (also known as -autocommit feature in other DBMSes). In other words, each user statement is -executed in its own transaction and commit is implicit (if execution was -successfull). BEGIN initiates a user transaction in chained mode, i.e. all -user statements after BEGIN command will be executed in single transaction -untill explicit COMMIT, ROLLBACK or execution abort. Statements in chained -mode are executed much faster, because of transaction start/commit requires -significant CPU and disk activity. This mode is also required for -consistency when changing one of related tables. - -Default transaction isolation level in Postgres is READ COMMITTED one, when -queries inside transaction see only changes committed before query -execution. So, you have to use SET TRANSACTION ISOLATION LEVEL SERIALIZABLE -command just after BEGIN if you need in better transaction isolation. In -SERIALIZABLE mode queries will see only changes committed before entire -transaction began (actually, before execution of first DML statement in -serializable transaction). - -If the transaction is committed, Postgres will ensure either that all -updates are done or else that none of them are done. Transactions have the -standard ACID (atomic, consistent, isolatable, and durable) property. - -\fBNote\fR: There is no explicit BEGIN command in SQL92; transaction -initiation is always implicit and it terminates either with a COMMIT or with -a ROLLBACK statement (i.e. all transactions are chained). SQL92 also -requires SERIALIZABLE to be default transaction isolation level. - -.SH "SEE ALSO" -rollback(l), -commit(l), -set(l), -lock(l). |