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Special Forums UNIX and Linux Applications Infrastructure Monitoring Possible performance improvement (Bash and flat file) Post 302420468 by Corona688 on Tuesday 11th of May 2010 06:05:54 PM
Old 05-11-2010
Quote:
Originally Posted by prafulnama
Thanks!

@Corona: I could use the 'split array' for retrieving a specific word from a string but for retrieving a substring, is there an alternative to
Code:
something=`echo $line | cut -d ' ' -f $start-$end`

A substring is
Code:
${VARNAME:START:LENGTH}

Expressions are allowed in there, so
Code:
${VARNAME:$START:((END-START))}

 

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START 
TRANSACTION(7) SQL Commands START TRANSACTION(7) NAME
START TRANSACTION - start a transaction block SYNOPSIS
START TRANSACTION [ transaction_mode [, ...] ] where transaction_mode is one of: ISOLATION LEVEL { SERIALIZABLE | REPEATABLE READ | READ COMMITTED | READ UNCOMMITTED } READ WRITE | READ ONLY DESCRIPTION
This command begins a new transaction block. If the isolation level or read/write mode is specified, the new transaction has those charac- teristics, as if SET TRANSACTION [set_transaction(7)] was executed. This is the same as the BEGIN [begin(7)] command. PARAMETERS
Refer to SET TRANSACTION [set_transaction(7)] for information on the meaning of the parameters to this statement. COMPATIBILITY
In the standard, it is not necessary to issue START TRANSACTION to start a transaction block: any SQL command implicitly begins a block. PostgreSQL's behavior can be seen as implicitly issuing a COMMIT after each command that does not follow START TRANSACTION (or BEGIN), and it is therefore often called ``autocommit''. Other relational database systems might offer an autocommit feature as a convenience. The SQL standard requires commas between successive transaction_modes, but for historical reasons PostgreSQL allows the commas to be omit- ted. See also the compatibility section of SET TRANSACTION [set_transaction(7)]. SEE ALSO
BEGIN [begin(7)], COMMIT [commit(7)], ROLLBACK [rollback(7)], SAVEPOINT [savepoint(7)], SET TRANSACTION [set_transaction(7)] SQL - Language Statements 2010-05-14 START TRANSACTION(7)
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