class Blazer::Adapters::SqlAdapter

Attributes

connection_model[R]

Public Class Methods

name() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 11
def self.name
  "Blazer::Connection::Adapter#{object_id}"
end
new(data_source) click to toggle source
Calls superclass method Blazer::Adapters::BaseAdapter::new
# File lib/blazer/adapters/sql_adapter.rb, line 6
def initialize(data_source)
  super

  @connection_model =
    Class.new(Blazer::Connection) do
      def self.name
        "Blazer::Connection::Adapter#{object_id}"
      end
      establish_connection(data_source.settings["url"]) if data_source.settings["url"]
    end
end

Public Instance Methods

cachable?(statement) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 104
def cachable?(statement)
  !%w[CREATE ALTER UPDATE INSERT DELETE].include?(statement.split.first.to_s.upcase)
end
cancel(run_id) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 93
def cancel(run_id)
  if postgresql?
    select_all("SELECT pg_cancel_backend(pid) FROM pg_stat_activity WHERE pid <> pg_backend_pid() AND query LIKE '%,run_id:#{run_id}%'")
  elsif redshift?
    first_row = select_all("SELECT pid FROM stv_recents WHERE status = 'Running' AND query LIKE '%,run_id:#{run_id}%'").first
    if first_row
      select_all("CANCEL #{first_row["pid"].to_i}")
    end
  end
end
cost(statement) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 67
def cost(statement)
  result = explain(statement)
  if sqlserver?
    result["TotalSubtreeCost"]
  else
    match = /cost=\d+\.\d+..(\d+\.\d+) /.match(result)
    match[1] if match
  end
end
explain(statement) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 77
def explain(statement)
  if postgresql? || redshift?
    select_all("EXPLAIN #{statement}").rows.first.first
  elsif sqlserver?
    begin
      execute("SET SHOWPLAN_ALL ON")
      result = select_all(statement).each.first
    ensure
      execute("SET SHOWPLAN_ALL OFF")
    end
    result
  end
rescue
  nil
end
preview_statement() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 53
def preview_statement
  if postgresql?
    "SELECT * FROM \"{table}\" LIMIT 10"
  elsif sqlserver?
    "SELECT TOP (10) * FROM {table}"
  else
    "SELECT * FROM {table} LIMIT 10"
  end
end
reconnect() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 63
def reconnect
  connection_model.establish_connection(settings["url"])
end
run_statement(statement, comment) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 18
def run_statement(statement, comment)
  columns = []
  rows = []
  error = nil

  begin
    in_transaction do
      set_timeout(data_source.timeout) if data_source.timeout

      result = select_all("#{statement} /*#{comment}*/")
      columns = result.columns
      cast_method = Rails::VERSION::MAJOR < 5 ? :type_cast : :cast_value
      result.rows.each do |untyped_row|
        rows << (result.column_types.empty? ? untyped_row : columns.each_with_index.map { |c, i| untyped_row[i] ? result.column_types[c].send(cast_method, untyped_row[i]) : untyped_row[i] })
      end
    end
  rescue => e
    error = e.message.sub(/.+ERROR: /, "")
    error = Blazer::TIMEOUT_MESSAGE if Blazer::TIMEOUT_ERRORS.any? { |e| error.include?(e) }
    reconnect if error.include?("PG::ConnectionBad")
  end

  [columns, rows, error]
end
schema() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 48
def schema
  result = data_source.run_statement(connection_model.send(:sanitize_sql_array, ["SELECT table_schema, table_name, column_name, data_type, ordinal_position FROM information_schema.columns WHERE table_schema IN (?) ORDER BY 1, 2", schemas]))
  result.rows.group_by { |r| [r[0], r[1]] }.map { |k, vs| {schema: k[0], table: k[1], columns: vs.sort_by { |v| v[2] }.map { |v| {name: v[2], data_type: v[3]} }} }
end
tables() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 43
def tables
  result = data_source.run_statement(connection_model.send(:sanitize_sql_array, ["SELECT table_name FROM information_schema.tables WHERE table_schema IN (?) ORDER BY table_name", schemas]), refresh_cache: true)
  result.rows.map(&:first)
end

Protected Instance Methods

adapter_name() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 135
def adapter_name
  # prevent bad data source from taking down queries/new
  connection_model.connection.adapter_name rescue nil
end
default_schema() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 144
def default_schema
  if postgresql? || redshift?
    "public"
  elsif sqlserver?
    "dbo"
  else
    connection_model.connection_config[:database]
  end
end
execute(statement) click to toggle source

seperate from select_all to prevent mysql error

# File lib/blazer/adapters/sql_adapter.rb, line 115
def execute(statement)
  connection_model.connection.execute(statement)
end
in_transaction() { || ... } click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 168
def in_transaction
  connection_model.connection_pool.with_connection do
    if use_transaction?
      connection_model.transaction do
        yield
        raise ActiveRecord::Rollback
      end
    else
      yield
    end
  end
end
mysql?() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 127
def mysql?
  ["MySQL", "Mysql2", "Mysql2Spatial"].include?(adapter_name)
end
postgresql?() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 119
def postgresql?
  ["PostgreSQL", "PostGIS"].include?(adapter_name)
end
redshift?() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 123
def redshift?
  ["Redshift"].include?(adapter_name)
end
schemas() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 140
def schemas
  settings["schemas"] || [connection_model.connection_config[:schema] || default_schema]
end
select_all(statement) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 110
def select_all(statement)
  connection_model.connection.select_all(statement)
end
set_timeout(timeout) click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 154
def set_timeout(timeout)
  if postgresql? || redshift?
    execute("SET #{use_transaction? ? "LOCAL " : ""}statement_timeout = #{timeout.to_i * 1000}")
  elsif mysql?
    execute("SET max_execution_time = #{timeout.to_i * 1000}")
  else
    raise Blazer::TimeoutNotSupported, "Timeout not supported for #{adapter_name} adapter"
  end
end
sqlserver?() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 131
def sqlserver?
  ["SQLServer", "tinytds", "mssql"].include?(adapter_name)
end
use_transaction?() click to toggle source
# File lib/blazer/adapters/sql_adapter.rb, line 164
def use_transaction?
  settings.key?("use_transaction") ? settings["use_transaction"] : true
end