Module: MonetDB::Connection::Query

Included in:
MonetDB::Connection
Defined in:
lib/monetdb/connection/query.rb

Instance Method Summary collapse

Instance Method Details

#query(statement) ⇒ Object Also known as: select_rows

Raises:



5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
 
# File 'lib/monetdb/connection/query.rb', line 5

def query(statement)
  raise ConnectionError, "Not connected to server" unless connected?

  start = Time.now

  write "s#{statement};"
  response = read.split("\n")

  log :info, "\n  SQL (#{((Time.now - start) * 1000).round(1)}ms)  #{statement}"

  query_header, table_header = extract_headers!(response)

  if query_header[:type] == Q_TABLE
    unless query_header[:rows] == response.size
      raise QueryError, "Amount of fetched rows does not match header value (#{response.size} instead of #{query_header[:rows]})"
    end
    response = parse_rows(query_header, table_header, response.join("\n"))
  else
    response = true
  end

  response
end

#select_value(query) ⇒ Object 



35
36
37
38
 
# File 'lib/monetdb/connection/query.rb', line 35

def select_value(query)
  row = select_rows(query)[0]
  row[0] if row
end

#select_values(query) ⇒ Object 



31
32
33
 
# File 'lib/monetdb/connection/query.rb', line 31

def select_values(query)
  select_rows(query).collect{|x| x[0]}
end