From 8338bb049db44d9b470b2a76acc5853b92915238 Mon Sep 17 00:00:00 2001 From: Boris Kolpackov Date: Wed, 17 Oct 2012 09:31:54 +0200 Subject: Add example for prepared query usage --- prepared/README | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 prepared/README (limited to 'prepared/README') diff --git a/prepared/README b/prepared/README new file mode 100644 index 0000000..1fc6a0f --- /dev/null +++ b/prepared/README @@ -0,0 +1,65 @@ +This example shows how to use prepared queries. In particular, it includes +examples of cached and uncached queries, with and without by-reference +parameters, as well as the use of a prepared query factory. + +The example consists of the following files: + +person.hxx + Header file defining the 'person' persistent class as well as the + 'person_count' view. + +person-odb.hxx +person-odb.ixx +person-odb.cxx +person.sql + The first three files contain the database support code and the last file + contains the database schema for the person.hxx header. + + These files are generated by the ODB compiler from person.hxx using the + following command line: + + odb -d --generate-query --generate-prepared \ +--generate-schema person.hxx + + Where stands for the database system we are using, for example, + 'mysql'. + + The --generate-prepared option requests the generation of the prepared + query support code. + +database.hxx + Contains the create_database() function which instantiates the concrete + database class corresponding to the database system we are using. + +driver.cxx + Driver for the example. It includes the person.hxx and person-odb.hxx + headers to gain access to the persistent classes and their database support + code. It also includes database.hxx for the create_database() function + declaration. + + In main() the driver first calls create_database() to obtain the database + instance and creates a number of persistent objects. It then prepares and + executes a number of queries to illustrate various usage scenarios. + +To compile and link the example manually from the command line we can use +the following commands (using MySQL as an example; replace 'c++' with your +C++ compiler name): + +c++ -c person-odb.cxx +c++ -DDATABASE_MYSQL -c driver.cxx +c++ -o driver driver.o person-odb.o -lodb-mysql -lodb + +To run the example we may first need to create the database schema (for some +database systems, such as SQLite, the schema is embedded into the generated +code which makes this step unnecessary). Using MySQL as an example, this +can be achieved with the following command: + +mysql --user=odb_test --database=odb_test < person.sql + +Here we use 'odb_test' as the database login and also 'odb_test' as the +database name. + +Once the database schema is ready, we can run the example (using MySQL as +the database): + +./driver --user odb_test --database odb_test -- cgit v1.1