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Committer: Marisa Plumb
Date: 2011-03-17 16:33:45 UTC
mto: This revision was merged to the branch mainline in revision 2283.
Revision ID: marisa.plumb@gmail.com-20110317163345-c9eslo1ipelgdr7x

doc fixes and additions

files added:
docs/load_data_infile.rst

files modified:
docs/dml.rst

docs/dynamic.rst

docs/functions/overview.rst

docs/installing/from_source.rst

docs/truncate.rst

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docs/dynamic.rst

Dynamic SQL allows you to execute DDL statements (and other SQL statements) that are not supported in purely static SQL programs.

EXECUTE

--------

EXECUTE() is used to generate SQL in a dynamic manner on the server. It can select values inside of the database as variables, and then execute them from statements that are already stored as variables.

EXECUTE can be CONCURRENT and with NO RETURN.

In Drizzle you can use the EXECUTE command along with :doc:'user defined variables <variables>'

to create SQL in a dynamic manner on the server. An exmaple of this is:

to create SQL in a dynamic manner on the server. An example of this is:

.. code-block:: mysql

launched it. It can be killed via KILL and the system limit on total number

of sessions will be enforced.

.. todo::

EXECUTE executes the statements inside an explicit transaction.

EXECUTE also executes the statements inside an explicit transaction.

The EXECUTE class has a run() method, which takes a std::string with SQL (to execute). Here is a simple example from the slave plugin code:

.. code-block:: mysql

Execute execute(*(_session.get()), true);

string sql("SELECT `transaction_id` FROM `sys-replication`.`queue`"

" WHERE `commit_order` IS NOT NULL ORDER BY `commit_order` ASC");

sql::ResultSet result_set(1);

execute.run(sql, result_set);

In essence, EXECUTE wraps SQL (single or multiple statements) in a transaction and executes it.

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