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Re: R: transactions and UNLOCK TABLES

 

Thank you for your clarification, Elena. Based on this information, I find the MySQL manual confusing, so I have reported a bug:

http://bugs.mysql.com/bug.php?id=74033

Unless it turns out that I'm still missing something, I will also check the kb.

Regards
Federico


--------------------------------------------
Mar 23/9/14, Elena Stepanova <elenst@xxxxxxxxxxxxxxxx> ha scritto:

 Oggetto: Re: [Maria-discuss] R: transactions and UNLOCK TABLES
 A: "Federico Razzoli" <federico_raz@xxxxxxxx>, maria-discuss@xxxxxxxxxxxxxxxxxxx
 Data: Martedì 23 settembre 2014, 11:51
 
 Hi Federico,
 
 On 23.09.2014 12:50, Federico
 Razzoli wrote:
 > Let's make the
 snippet simpler. Only one table, non-transactional, please
 look at the difference from what docs say and the real
 behaviour. If one could explain what UNLOCK TABLES exactly
 does, it would be great.
 >
 > MariaDB [test]> SELECT
 @@in_transaction, @@autocommit;
 >
 +------------------+--------------+
 > |
 @@in_transaction | @@autocommit |
 >
 +------------------+--------------+
 > | 
               0 |            1 |
 > +------------------+--------------+
 > 1 row in set (0.00 sec)
 >
 > MariaDB [test]>
 CREATE OR REPLACE TABLE t (c INT) ENGINE = MEMORY;
 > Query OK, 0 rows affected (0.12 sec)
 >
 > MariaDB [test]>
 LOCK TABLE t WRITE;
 > Query OK, 0 rows
 affected (0.00 sec)
 >
 > MariaDB [test]> START TRANSACTION;
 > Query OK, 0 rows affected (0.00 sec)
 
 "Beginning a transaction
 causes table locks acquired with LOCK TABLES to 
 be released, as though you had executed UNLOCK
 TABLES."
 
 http://dev.mysql.com/doc/refman/5.5/en/commit.html
 
 >
 >
 MariaDB [test]> INSERT INTO t VALUES (1);
 > Query OK, 1 row affected (0.01 sec)
 >
 > MariaDB [test]>
 UNLOCK TABLES;
 > Query OK, 0 rows
 affected (0.00 sec)
 
 So,
 this UNLOCK is not actually doing anything.
 
 Regards,
 Elena
 
 >
 > MariaDB [test]> SELECT
 @@in_transaction;
 >
 +------------------+
 > | @@in_transaction
 |
 > +------------------+
 > |                1 |
 > +------------------+
 >
 1 row in set (0.00 sec)
 >
 >
 > Regards
 > Federico
 >
 >
 >
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