=SQL Anywhere DBD Driver for Ruby-DBI
This is a SQL Anywhere driver for Ruby DBI (http://ruby-dbi.rubyforge.org/). This driver requires the native SQL Anywhere Ruby driver. To get the native driver, use:
gem install sqlanywhere
This driver is designed for use with DBI 0.4 and greater.
This driver is licensed under the Apache License, Version 2.
The official code repository is located on GitHub. The repository can be cloned with:
git clone git://github.com/sqlanywhere/dbd-sqlanywhere.git
==Making a Connection
The following code is a sample database configuration object that connects to a database called 'Test'.
require 'dbi'
DBI.connect('DBI:SQLAnywhere:Test') do | dbh | if dbh.ping print "Successfully Connected" end end
The connection function takes the general form:
dbh = DBI.connect(DBNAME, [USER_NAME], [PASSWORD])
The DBNAME string can be specified in the following forms:
"DBI:SQLAnywhere:" "DBI:SQLAnywhere:{ENG}" "DBI:SQLAnywhere:{ENG}:{DBN}" "DBI:SQLAnywhere:{CONNECTION_STRING}" # where CONNECTION_STRING ~= "key1=val1;key2=val2;..."
For the first form, nothing will be added to the connection string. With the second and third forms the driver will add ENG and DBN to the connection string accordingly. The fourth form will pass the supplied connection string through unmolested.
The USER_NAME and PASSWORD can be passed into the function and they will be automatically appended to the connection string. Since Ruby DBI will automatically fill in the username and password with defaults if they are omitted, you should NEVER include a "UID=" or "PWD=" in your connection string or an exception will be thrown.
Examples:
DBI.connect("DBI:SQLAnywhere:") ==> "uid=dba;pwd=sql" DBI.connect("DBI:SQLAnywhere:Demo") ==> "eng=Demo;uid=dba;pwd=sql" DBI.connect("DBI:SQLAnywhere:Demo:Test") ==> "eng=Demo;dbn=Test;uid=dba;pwd=sql" DBI.connect("DBI:SQLAnywhere:Demo:Test", 'john', 'doe') ==> "eng=Demo;dbn=Test;uid=john;pwd=doe" DBI.connect("DBI:SQLAnywhere:eng=Demo;dbn=Test") ==> "eng=Demo;dbn=Test;uid=dba;pwd=sql" DBI.connect("DBI:SQLAnywhere:eng=Demo;dbn=Test;uid=john") ==> EXCEPTION! UID cannot be specified in the connection string DBI.connect("DBI:SQLAnywhere:CommLinks=tcpip(port=2638)") ==> "CommLinks=tcpip(port=2638);uid=dba;pwd=sql"
==Running Test Suite
For information on running the Ruby/DBI DBD Tests, please see
test/DBD_TESTS
==Driver-Specific Features
At the time of this writing, there was no standard way to handle INOUT and OUT parameters from stored procedures in DBI.
When binding to an OUT parameter, you must bind a hash that contains a key called :name. This :name will be used to retrieve the OUT value after execution. If the OUT column is of string or binary type, you must also pass a key called :length with the expected maximum length of the OUT parameter.
In the case of an INOUT parameter, the :name and :length keys are the same as for OUT parameters, but an additional :value parameter holds the value to be passed into the stored procedure.
After execution, you can use the statement-specific function :bound_param to retrieve the output value using the :name supplied at binding time.
===Example of using OUT and INOUT parameters
require 'dbi'
begin DBI.connect("DBI:SQLAnywhere:test") do |dbh|
sql = <<SQL IF EXISTS(SELECT * FROM SYS.SYSPROCEDURE where proc_name = 'foo') THEN DROP PROCEDURE foo; END IF SQL
dbh.do(sql);
sql = <<SQL
create procedure foo
( IN prefix char(10),
INOUT buffer varchar(256),
OUT str_len int,
IN suffix char(10)
)
begin
set buffer = prefix || buffer || suffix;
select length( buffer ) into str_len;
end
SQL
dbh.do(sql);
buffer = "-some_string-"
prefix = "PREFIX"
# preparing the statement
sth = dbh.prepare("call foo( ?, ?, ?, ? )")
# Binding buffer column as :buf, and str_len column as :len
# Note that we must supply a :value for :buf since it is an INOUT
# And we must supply a :length for :buf since it is a string column
sth.execute( prefix, {:name => :buf, :value => buffer, :length => 255}, {:name => :len}, "SUFFIX")
# Retrieve the OUT value from buffer
new_buffer = sth.func(:bound_param, :buf)
# Retrieve the OUT value from str_len
length = sth.func(:bound_param, :len)
puts "Complete string is #{new_buffer} and is #{length} chars long"
# Add the results back into the string, and re-execute
sth.execute("PREFIX", {:name => :buf, :value => new_buffer, :length => 255}, {:name => :len}, "SUFFIX")
new_buffer = sth.func(:bound_param, :buf)
length = sth.func(:bound_param, :len)
puts "Complete string is #{new_buffer} and is #{length} chars long"
end
rescue DBI::DatabaseError => e puts "An error occurred" puts "Error code: #{e.err}" puts "Error message: #{e.errstr}" puts "Error SQLSTATE: #{e.state}" ensure DBI.disconnect_all end