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diff --git a/user_guide_src/source/database/transactions.rst b/user_guide_src/source/database/transactions.rst deleted file mode 100644 index cfd6a566d..000000000 --- a/user_guide_src/source/database/transactions.rst +++ /dev/null @@ -1,127 +0,0 @@ -############ -Transactions -############ - -CodeIgniter's database abstraction allows you to use transactions with -databases that support transaction-safe table types. In MySQL, you'll -need to be running InnoDB or BDB table types rather than the more common -MyISAM. Most other database platforms support transactions natively. - -If you are not familiar with transactions we recommend you find a good -online resource to learn about them for your particular database. The -information below assumes you have a basic understanding of -transactions. - -CodeIgniter's Approach to Transactions -====================================== - -CodeIgniter utilizes an approach to transactions that is very similar to -the process used by the popular database class ADODB. We've chosen that -approach because it greatly simplifies the process of running -transactions. In most cases all that is required are two lines of code. - -Traditionally, transactions have required a fair amount of work to -implement since they demand that you keep track of your queries and -determine whether to commit or rollback based on the success or failure -of your queries. This is particularly cumbersome with nested queries. In -contrast, we've implemented a smart transaction system that does all -this for you automatically (you can also manage your transactions -manually if you choose to, but there's really no benefit). - -Running Transactions -==================== - -To run your queries using transactions you will use the -$this->db->trans_start() and $this->db->trans_complete() functions as -follows:: - - $this->db->trans_start(); - $this->db->query('AN SQL QUERY...'); - $this->db->query('ANOTHER QUERY...'); - $this->db->query('AND YET ANOTHER QUERY...'); - $this->db->trans_complete(); - -You can run as many queries as you want between the start/complete -functions and they will all be committed or rolled back based on success -or failure of any given query. - -Strict Mode -=========== - -By default CodeIgniter runs all transactions in Strict Mode. When strict -mode is enabled, if you are running multiple groups of transactions, if -one group fails all groups will be rolled back. If strict mode is -disabled, each group is treated independently, meaning a failure of one -group will not affect any others. - -Strict Mode can be disabled as follows:: - - $this->db->trans_strict(FALSE); - -Managing Errors -=============== - -If you have error reporting enabled in your config/database.php file -you'll see a standard error message if the commit was unsuccessful. If -debugging is turned off, you can manage your own errors like this:: - - $this->db->trans_start(); - $this->db->query('AN SQL QUERY...'); - $this->db->query('ANOTHER QUERY...'); - $this->db->trans_complete(); - - if ($this->db->trans_status() === FALSE) - { - // generate an error... or use the log_message() function to log your error - } - -Disabling Transactions -====================== - -If you would like to disable transactions you can do so using -``$this->db->trans_off()``:: - - $this->db->trans_off(); - - $this->db->trans_start(); - $this->db->query('AN SQL QUERY...'); - $this->db->trans_complete(); - -When transactions are disabled, your queries will be auto-committed, just as -they are when running queries without transactions, practically ignoring -any calls to ``trans_start()``, ``trans_complete()``, etc. - -Test Mode -========= - -You can optionally put the transaction system into "test mode", which -will cause your queries to be rolled back -- even if the queries produce -a valid result. To use test mode simply set the first parameter in the -$this->db->trans_start() function to TRUE:: - - $this->db->trans_start(TRUE); // Query will be rolled back - $this->db->query('AN SQL QUERY...'); - $this->db->trans_complete(); - -Running Transactions Manually -============================= - -If you would like to run transactions manually you can do so as follows:: - - $this->db->trans_begin(); - - $this->db->query('AN SQL QUERY...'); - $this->db->query('ANOTHER QUERY...'); - $this->db->query('AND YET ANOTHER QUERY...'); - - if ($this->db->trans_status() === FALSE) - { - $this->db->trans_rollback(); - } - else - { - $this->db->trans_commit(); - } - -.. note:: Make sure to use $this->db->trans_begin() when running manual - transactions, **NOT** $this->db->trans_start(). |