require 'db2/db2cli.rb'
module DB2
module DB2Util
include DB2CLI
def free() SQLFreeHandle(@handle_type, @handle); end
def handle() @handle; end
def check_rc(rc)
if rc != SQL_SUCCESS and rc != SQL_SUCCESS_WITH_INFO and rc != SQL_NO_DATA_FOUND
rec = 1
msg = ''
loop do
a = SQLGetDiagRec(@handle_type, @handle, rec, 500)
break if a[0] != SQL_SUCCESS
msg << a[3] if !a[3].nil? and a[3] != '' # Create message.
rec += 1
end
raise "DB2 error: #{msg}"
end
end
end
class Environment
include DB2Util
def initialize
@handle_type = SQL_HANDLE_ENV
rc, @handle = SQLAllocHandle(@handle_type, SQL_NULL_HANDLE)
check_rc(rc)
end
def data_sources(buffer_length = 1024)
retval = []
max_buffer_length = buffer_length
a = SQLDataSources(@handle, SQL_FETCH_FIRST, SQL_MAX_DSN_LENGTH + 1, buffer_length)
retval << [a[1], a[3]]
max_buffer_length = [max_buffer_length, a[4]].max
loop do
a = SQLDataSources(@handle, SQL_FETCH_NEXT, SQL_MAX_DSN_LENGTH + 1, buffer_length)
break if a[0] == SQL_NO_DATA_FOUND
retval << [a[1], a[3]]
max_buffer_length = [max_buffer_length, a[4]].max
end
if max_buffer_length > buffer_length
get_data_sources(max_buffer_length)
else
retval
end
end
end
class Connection
include DB2Util
def initialize(environment)
@env = environment
@handle_type = SQL_HANDLE_DBC
rc, @handle = SQLAllocHandle(@handle_type, @env.handle)
check_rc(rc)
end
def connect(server_name, user_name = '', auth = '')
check_rc(SQLConnect(@handle, server_name, user_name, auth))
end
def set_connect_attr(attr, value)
value += "\0" if value.class == String
check_rc(SQLSetConnectAttr(@handle, attr, value))
end
def set_auto_commit_on
set_connect_attr(SQL_ATTR_AUTOCOMMIT, SQL_AUTOCOMMIT_ON)
end
def set_auto_commit_off
set_connect_attr(SQL_ATTR_AUTOCOMMIT, SQL_AUTOCOMMIT_OFF)
end
def disconnect
check_rc(SQLDisconnect(@handle))
end
def rollback
check_rc(SQLEndTran(@handle_type, @handle, SQL_ROLLBACK))
end
def commit
check_rc(SQLEndTran(@handle_type, @handle, SQL_COMMIT))
end
end
class Statement
include DB2Util
def initialize(connection)
@conn = connection
@handle_type = SQL_HANDLE_STMT
@parms = [] #yun
@sql = '' #yun
@numParms = 0 #yun
@prepared = false #yun
@parmArray = [] #yun. attributes of the parameter markers
rc, @handle = SQLAllocHandle(@handle_type, @conn.handle)
check_rc(rc)
end
def columns(table_name)
check_rc(SQLColumns(@handle, "", "%", table_name, "%"))
fetch_all
end
def tables
check_rc(SQLTables(@handle, "", "%", "%", "TABLE"))
fetch_all
end
def prepare(sql)
@sql = sql
check_rc(SQLPrepare(@handle, sql))
rc, @numParms = SQLNumParams(@handle) #number of question marks
check_rc(rc)
#--------------------------------------------------------------------------
# parameter attributes are stored in instance variable @parmArray so that
# they are available when execute method is called.
#--------------------------------------------------------------------------
if @numParms > 0 # get parameter marker attributes
1.upto(@numParms) do |i| # parameter number starts from 1
rc, type, size, decimalDigits = SQLDescribeParam(@handle, i)
check_rc(rc)
@parmArray << Parameter.new(type, size, decimalDigits)
end
end
@prepared = true
self
end
def execute(*parms)
raise "The statement was not prepared" if @prepared == false
if parms.size == 1 and parms[0].class == Array
parms = parms[0]
end
if @numParms != parms.size
raise "Number of parameters supplied does not match with the SQL statement"
end
if @numParms > 0 #need to bind parameters
#--------------------------------------------------------------------
#calling bindParms may not be safe. Look comment below.
#--------------------------------------------------------------------
#bindParms(parms)
valueArray = []
1.upto(@numParms) do |i| # parameter number starts from 1
type = @parmArray[i - 1].class
size = @parmArray[i - 1].size
decimalDigits = @parmArray[i - 1].decimalDigits
if parms[i - 1].class == String
valueArray << parms[i - 1]
else
valueArray << parms[i - 1].to_s
end
rc = SQLBindParameter(@handle, i, type, size, decimalDigits, valueArray[i - 1])
check_rc(rc)
end
end
check_rc(SQLExecute(@handle))
if @numParms != 0
check_rc(SQLFreeStmt(@handle, SQL_RESET_PARAMS)) # Reset parameters
end
self
end
#-------------------------------------------------------------------------------
# The last argument(value) to SQLBindParameter is a deferred argument, that is,
# it should be available when SQLExecute is called. Even though "value" is
# local to bindParms method, it seems that it is available when SQLExecute
# is called. I am not sure whether it would still work if garbage collection
# is done between bindParms call and SQLExecute call inside the execute method
# above.
#-------------------------------------------------------------------------------
def bindParms(parms) # This is the real thing. It uses SQLBindParms
1.upto(@numParms) do |i| # parameter number starts from 1
rc, dataType, parmSize, decimalDigits = SQLDescribeParam(@handle, i)
check_rc(rc)
if parms[i - 1].class == String
value = parms[i - 1]
else
value = parms[i - 1].to_s
end
rc = SQLBindParameter(@handle, i, dataType, parmSize, decimalDigits, value)
check_rc(rc)
end
end
#------------------------------------------------------------------------------
# bind method does not use DB2's SQLBindParams, but replaces "?" in the
# SQL statement with the value before passing the SQL statement to DB2.
# It is not efficient and can handle only strings since it puts everything in
# quotes.
#------------------------------------------------------------------------------
def bind(sql, args) #does not use SQLBindParams
arg_index = 0
result = ""
tokens(sql).each do |part|
case part
when '?'
result << "'" + (args[arg_index]) + "'" #put it into quotes
arg_index += 1
when '??'
result << "?"
else
result << part
end
end
if arg_index < args.size
raise "Too many SQL parameters"
elsif arg_index > args.size
raise "Not enough SQL parameters"
end
result
end
## Break the sql string into parts.
#
# This is NOT a full lexer for SQL. It just breaks up the SQL
# string enough so that question marks, double question marks and
# quoted strings are separated. This is used when binding
# arguments to "?" in the SQL string. Note: comments are not
# handled.
#
def tokens(sql)
toks = sql.scan(/('([^'\\]|''|\\.)*'|"([^"\\]|""|\\.)*"|\?\??|[^'"?]+)/)
toks.collect { |t| t[0] }
end
def exec_direct(sql)
check_rc(SQLExecDirect(@handle, sql))
self
end
def set_cursor_name(name)
check_rc(SQLSetCursorName(@handle, name))
self
end
def get_cursor_name
rc, name = SQLGetCursorName(@handle)
check_rc(rc)
name
end
def row_count
rc, rowcount = SQLRowCount(@handle)
check_rc(rc)
rowcount
end
def num_result_cols
rc, cols = SQLNumResultCols(@handle)
check_rc(rc)
cols
end
def fetch_all
if block_given?
while row = fetch do
yield row
end
else
res = []
while row = fetch do
res << row
end
res
end
end
def fetch
cols = get_col_desc
rc = SQLFetch(@handle)
if rc == SQL_NO_DATA_FOUND
SQLFreeStmt(@handle, SQL_CLOSE) # Close cursor
SQLFreeStmt(@handle, SQL_RESET_PARAMS) # Reset parameters
return nil
end
raise "ERROR" unless rc == SQL_SUCCESS
retval = []
cols.each_with_index do |c, i|
rc, content = SQLGetData(@handle, i + 1, c[1], c[2] + 1) #yun added 1 to c[2]
retval << adjust_content(content)
end
retval
end
def fetch_as_hash
cols = get_col_desc
rc = SQLFetch(@handle)
if rc == SQL_NO_DATA_FOUND
SQLFreeStmt(@handle, SQL_CLOSE) # Close cursor
SQLFreeStmt(@handle, SQL_RESET_PARAMS) # Reset parameters
return nil
end
raise "ERROR" unless rc == SQL_SUCCESS
retval = {}
cols.each_with_index do |c, i|
rc, content = SQLGetData(@handle, i + 1, c[1], c[2] + 1) #yun added 1 to c[2]
retval[c[0]] = adjust_content(content)
end
retval
end
def get_col_desc
rc, nr_cols = SQLNumResultCols(@handle)
cols = (1..nr_cols).collect do |c|
rc, name, bl, type, col_sz = SQLDescribeCol(@handle, c, 1024)
[name.downcase, type, col_sz]
end
end
def adjust_content(c)
case c.class.to_s
when 'DB2CLI::NullClass'
return nil
when 'DB2CLI::Time'
"%02d:%02d:%02d" % [c.hour, c.minute, c.second]
when 'DB2CLI::Date'
"%04d-%02d-%02d" % [c.year, c.month, c.day]
when 'DB2CLI::Timestamp'
"%04d-%02d-%02d %02d:%02d:%02d" % [c.year, c.month, c.day, c.hour, c.minute, c.second]
else
return c
end
end
end
class Parameter
attr_reader :type, :size, :decimalDigits
def initialize(type, size, decimalDigits)
@type, @size, @decimalDigits = type, size, decimalDigits
end
end
end
