Class: Arel::Visitors::MySQL

Inherits:
Object
  • Object
show all
Defined in:
lib/arel_extensions/visitors/mysql.rb

Constant Summary collapse

DATE_MAPPING = 
{
  'd' => 'DAY', 'm' => 'MONTH', 'w' => 'WEEK', 'y' => 'YEAR', 'wd' => 'WEEKDAY',
  'h' => 'HOUR', 'mn' => 'MINUTE', 's' => 'SECOND'
}.freeze
DATE_FORMAT_DIRECTIVES =

ISO C / POSIX

{ # ISO C / POSIX
  '%Y' => '%Y', '%C' =>   '', '%y' => '%y', '%m' => '%m', '%B' => '%M', '%b' => '%b', '%^b' => '%b',  # year, month
  '%d' => '%d', '%e' => '%e', '%j' => '%j', '%w' => '%w', '%A' => '%W',                               # day, weekday
  '%H' => '%H', '%k' => '%k', '%I' => '%I', '%l' => '%l', '%P' => '%p', '%p' => '%p',                 # hours
  '%M' => '%i', '%S' => '%S', '%L' =>   '', '%N' => '%f', '%z' => ''
}.freeze

Instance Method Summary collapse

Instance Method Details

#json_supported? ⇒ Boolean

JSON if implemented only after 10.2.3 (aggregations after 10.5.0) in MariaDb and 5.7 (aggregations after 5.7.22) in MySql

Returns:

  • (Boolean) 


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# File 'lib/arel_extensions/visitors/mysql.rb', line 448

def json_supported?
  version_supported?('10.5.0', '5.7.22')
end

#regexp_replace_supported? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arel_extensions/visitors/mysql.rb', line 456

def regexp_replace_supported?
  version_supported?('10.0.5', '8.0')
end

#version_supported?(mariadb_v = '10.2.3', mysql_v = '5.7.0') ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arel_extensions/visitors/mysql.rb', line 460

def version_supported?(mariadb_v = '10.2.3', mysql_v = '5.7.0')
  conn = Arel::Table.engine.connection
  conn.send(:mariadb?) && \
    (conn.respond_to?(:get_database_version) && conn.send(:get_database_version) >= mariadb_v || \
    conn.respond_to?(:version) && conn.send(:version) >= mariadb_v || \
    conn.instance_variable_get(:"@version") && conn.instance_variable_get(:"@version") >= mariadb_v) || \
    !conn.send(:mariadb?) && \
      (conn.respond_to?(:get_database_version) && conn.send(:get_database_version) >= mysql_v || \
      conn.respond_to?(:version) && conn.send(:version) >= mysql_v || \
      conn.instance_variable_get(:"@version") && conn.instance_variable_get(:"@version") >= mysql_v)
  # ideally we should parse the instance_variable @full_version because @version contains only the supposedly
  # corresponding mysql version of the current mariadb version (which is not very helpful most of the time)
end

#visit_Aggregate_For_AggregateFunction(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 408

def visit_Aggregate_For_AggregateFunction o, collector
  if !window_supported?
      warn("Warning : ArelExtensions: Window Functions are not available in the current version of the DBMS.")
      return collector
  end

  if !o.order.empty? || !o.group.empty?
    collector << " OVER ("
    if !o.group.empty?
      collector << " PARTITION BY ("
      visit o.group, collector
      collector << ")"
    end
    if !o.order.empty?
      collector << " ORDER BY ("
      visit o.order, collector
      collector << ")"
    end
    collector << ")"
  end
  collector
end

#visit_Arel_Nodes_As(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 349

def visit_Arel_Nodes_As o, collector
  if o.left.is_a?(Arel::Nodes::Binary)
    collector << '('
    collector = visit o.left, collector
    collector << ')'
  else
    collector = visit o.left, collector
  end
  collector << " AS `"
  collector = visit o.right, collector
  collector << "`"
  collector
end

#visit_Arel_Nodes_SelectStatement(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 340

def visit_Arel_Nodes_SelectStatement o, collector
  if !(collector.value.blank? || (collector.value.is_a?(Array) && collector.value[0].blank?)) && o.limit.blank? && o.offset.blank?
    o = o.dup
    o.orders = []
  end
  old_visit_Arel_Nodes_SelectStatement(o,collector)
end

#visit_ArelExtensions_Nodes_AiIMatches(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 65

def visit_ArelExtensions_Nodes_AiIMatches o, collector
  collector = visit o.left.ai_collate, collector
  collector << ' LIKE '
  collector = visit o.right.ai_collate, collector
  if o.escape
    collector << ' ESCAPE '
    visit o.escape, collector
  else
    collector
  end
end

#visit_ArelExtensions_Nodes_AiMatches(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 53

def visit_ArelExtensions_Nodes_AiMatches o, collector
  collector = visit o.left.ai_collate, collector
  collector << ' LIKE '
  collector = visit o.right.ai_collate, collector
  if o.escape
    collector << ' ESCAPE '
    visit o.escape, collector
  else
    collector
  end
end

#visit_ArelExtensions_Nodes_Cast(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 317

def visit_ArelExtensions_Nodes_Cast o, collector
  collector << "CAST("
  collector = visit o.left, collector
  collector << " AS "
  as_attr =
    Arel::Nodes::SqlLiteral.new(
      case o.as_attr
      when :string           then 'char'
      when :time             then 'time'
      when :int              then 'signed'
      when :number, :decimal then 'decimal(20,6)'
      when :datetime         then 'datetime'
      when :date             then 'date'
      when :binary           then 'binary'
      else                        o.as_attr.to_s
      end
    )
  collector = visit as_attr, collector
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_Collate(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 103

def visit_ArelExtensions_Nodes_Collate o, collector
  charset =
    case o.expressions.first
    when Arel::Attributes::Attribute
      case o.option
      when 'latin1','utf8'
        o.option
      else
        Arel::Table.engine.connection.charset || 'utf8'
      end
    else
      (o.option == 'latin1') ? 'latin1' : 'utf8'
    end
  collector = visit o.expressions.first, collector
  collector <<
    if o.ai
      " COLLATE #{charset == 'latin1' ? 'latin1_general_ci' : 'utf8_unicode_ci'}"
    # doesn't work in latin1
    elsif o.ci
      " COLLATE #{charset == 'latin1' ? 'latin1_general_ci' : 'utf8_unicode_ci'}"
    else
      " COLLATE #{charset}_bin"
    end
  collector
end

#visit_ArelExtensions_Nodes_Concat(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 129

def visit_ArelExtensions_Nodes_Concat o, collector
  collector << "CONCAT("
  o.expressions.each_with_index { |arg, i|
    collector << COMMA if i != 0
    if (arg.is_a?(Numeric)) || (arg.is_a?(Arel::Attributes::Attribute))
      collector << "CAST("
      collector = visit arg, collector
      collector << " AS char)"
    else
      collector = visit arg, collector
    end
  }
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_DateAdd(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 260

def visit_ArelExtensions_Nodes_DateAdd o, collector
  collector << "DATE_ADD("
  collector = visit o.left, collector
  collector << COMMA
  collector = visit o.mysql_value(o.right), collector
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_DateDiff(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 230

def visit_ArelExtensions_Nodes_DateDiff o, collector
  case o.right_node_type
  when :ruby_date, :ruby_time, :date, :datetime, :time
    collector <<
      case o.left_node_type
      when :ruby_time, :datetime, :time then 'TIMESTAMPDIFF(SECOND, '
      else                                   'DATEDIFF('
      end
    collector = visit o.right, collector
    collector << COMMA
    collector = visit o.left, collector
    collector << ")"
  else
    collector << '('
    collector = visit o.left, collector
    collector << ' - '
    if o.right.is_a?(ArelExtensions::Nodes::Duration)
      o.right.with_interval = true
      collector = visit o.right, collector
    else
      collector << '('
      collector = visit o.right, collector
      collector << ')'
    end
    collector << ')'
    collector
  end
  collector
end

#visit_ArelExtensions_Nodes_Duration(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 269

def visit_ArelExtensions_Nodes_Duration o, collector
  if o.left == 'wd'
    collector << "(WEEKDAY("
    collector = visit o.right, collector
    collector << ") + 1) % 7"
  else
    if o.with_interval
      case o.left
      when 'd','m','y'
        interval = 'DAY'
      when 'h','mn','s'
        interval = 'SECOND'
      when /i\z/
        interval = DATE_MAPPING[o.left[0..-2]]
      else
        interval = nil
      end
    end
    collector << " INTERVAL " if o.with_interval && interval
    collector << "#{DATE_MAPPING[o.left]}("
    collector = visit o.right, collector
    collector << ")"
    collector << " #{interval} " if o.with_interval && interval
  end
  collector
end

#visit_ArelExtensions_Nodes_Format(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 207

def visit_ArelExtensions_Nodes_Format o, collector
  case o.col_type
  when :date, :datetime, :time
    fmt = ArelExtensions::Visitors::strftime_to_format(o.iso_format, DATE_FORMAT_DIRECTIVES)
    collector << "DATE_FORMAT("
    collector = visit o.left, collector
    collector << COMMA
    collector = visit Arel::Nodes.build_quoted(fmt), collector
    collector << ")"
  when :integer, :float, :decimal
    collector << "FORMAT("
    collector = visit o.left, collector
    collector << Arel::Visitors::ToSql::COMMA
    collector << '2'
    collector << Arel::Visitors::ToSql::COMMA
    collector = visit o.right, collector
    collector << ")"
  else
    collector = visit o.left, collector
  end
  collector
end

#visit_ArelExtensions_Nodes_FormattedNumber(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 363

def visit_ArelExtensions_Nodes_FormattedNumber o, collector
  col = o.left.coalesce(0)
  params = o.locale ? [o.precision,Arel::Nodes.build_quoted(o.locale)] : [o.precision]
  sign = ArelExtensions::Nodes::Case.new.when(col<0).
            then('-').
            else(o.flags.include?('+') ? '+' : (o.flags.include?(' ') ? ' ' : ''))
  sign_length = ArelExtensions::Nodes::Length.new([sign])

  number =
    if o.scientific_notation
      ArelExtensions::Nodes::Concat.new([
              Arel::Nodes::NamedFunction.new('FORMAT',[
                col.abs/Arel::Nodes.build_quoted(10).pow(col.abs.log10.floor)
              ]+params),
              o.type,
              Arel::Nodes::NamedFunction.new('FORMAT',[
                col.abs.log10.floor,
                0
              ])
            ])
    else
      Arel::Nodes::NamedFunction.new('FORMAT',[col.abs]+params)
    end

  repeated_char = (o.width == 0) ? Arel::Nodes.build_quoted('') : ArelExtensions::Nodes::Case.new().
    when(Arel::Nodes.build_quoted(o.width).abs-(number.length+sign_length)>0).
    then(Arel::Nodes.build_quoted(
        o.flags.include?('-') ? ' ' : (o.flags.include?('0') ? '0' : ' ')
      ).repeat(Arel::Nodes.build_quoted(o.width).abs-(number.length+sign_length))
    ).
    else('')
  before = (!o.flags.include?('0'))&&(!o.flags.include?('-')) ? repeated_char : ''
  middle = (o.flags.include?('0'))&&(!o.flags.include?('-'))  ? repeated_char : ''
  after  = o.flags.include?('-') ? repeated_char : ''
  full_number = ArelExtensions::Nodes::Concat.new([
      before,
      sign,
      middle,
      number,
      after
    ])
  collector = visit ArelExtensions::Nodes::Concat.new([Arel::Nodes.build_quoted(o.prefix),full_number,Arel::Nodes.build_quoted(o.suffix)]), collector
  collector
end

#visit_ArelExtensions_Nodes_GroupConcat(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 145

def visit_ArelExtensions_Nodes_GroupConcat o, collector
  collector << "GROUP_CONCAT("
  collector = visit o.left, collector
  if !o.order.blank?
    collector << ' ORDER BY '
    o.order.each_with_index do |order,i|
      collector << Arel::Visitors::ToSql::COMMA if i != 0
      collector = visit order, collector
    end
  end
  if o.separator && o.separator != 'NULL'
    collector << ' SEPARATOR '
    collector = visit o.separator, collector
  end
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_IDoesNotMatch(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 89

def visit_ArelExtensions_Nodes_IDoesNotMatch o, collector
  collector << 'LOWER('
  collector = visit o.left, collector
  collector << ') NOT LIKE LOWER('
  collector = visit o.right, collector
  collector << ')'
  if o.escape
    collector << ' ESCAPE '
    visit o.escape, collector
  else
    collector
  end
end

#visit_ArelExtensions_Nodes_IMatches(o, collector) ⇒ Object

String functions



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# File 'lib/arel_extensions/visitors/mysql.rb', line 39

def visit_ArelExtensions_Nodes_IMatches o, collector # insensitive on ASCII
  collector << 'LOWER('
  collector = visit o.left, collector
  collector << ') LIKE LOWER('
  collector = visit o.right, collector
  collector << ')'
  if o.escape
    collector << ' ESCAPE '
    visit o.escape, collector
  else
    collector
  end
end

#visit_ArelExtensions_Nodes_IsNotNull(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 303

def visit_ArelExtensions_Nodes_IsNotNull o, collector
    collector << "NOT ISNULL("
    collector = visit o.expr, collector
    collector << ")"
    collector
end

#visit_ArelExtensions_Nodes_IsNull(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 296

def visit_ArelExtensions_Nodes_IsNull o, collector
  collector << "ISNULL("
  collector = visit o.expr, collector
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_Json(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 474

def visit_ArelExtensions_Nodes_Json o,collector
  return super if !json_supported?

  case o.dict
  when Array
    collector << 'JSON_ARRAY('
    o.dict.each.with_index do |v,i|
      if i != 0
        collector << COMMA
      end
      collector = visit v, collector
    end
    collector << ')'
  when Hash
    collector << 'JSON_OBJECT('
    o.dict.each.with_index do |(k,v),i|
      if i != 0
        collector << COMMA
      end
      collector = visit k, collector
      collector << COMMA
      collector = visit v, collector
    end
    collector << ')'
  else
    collector = visit o.dict, collector
  end
  collector
end

#visit_ArelExtensions_Nodes_JsonGet(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 516

def visit_ArelExtensions_Nodes_JsonGet o,collector
  collector << 'JSON_EXTRACT('
  collector = visit o.dict, collector
  collector << COMMA
  if o.key.is_a?(Integer)
    collector << "\"$[#{o.key}]\""
  else
    collector = visit Arel::Nodes.build_quoted('$.')+o.key, collector
  end
  collector << ')'
  collector
end

#visit_ArelExtensions_Nodes_JsonGroup(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 544

def visit_ArelExtensions_Nodes_JsonGroup o, collector
  return super if !json_supported?

  if o.as_array
    collector << 'JSON_ARRAYAGG('
    collector = visit o.dict, collector
    collector << ')'
  else
    case o.dict
    when Hash
      collector << 'JSON_MERGE_PATCH(' if o.dict.length > 1
      o.dict.each.with_index do |(k,v),i|
        if i != 0
          collector << COMMA
        end
        collector << 'JSON_OBJECTAGG('
        collector = visit k, collector
        collector << COMMA
        collector = visit v, collector
        collector << ')'
      end
      collector << ')' if o.dict.length > 1
    else
      collector << 'JSON_OBJECTAGG('
      collector = visit o.dict, collector
      collector << ')'
    end
  end
  collector
end

#visit_ArelExtensions_Nodes_JsonMerge(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 504

def visit_ArelExtensions_Nodes_JsonMerge o,collector
  collector << 'JSON_MERGE_PATCH('
  o.expressions.each.with_index do |v,i|
    if i != 0
      collector << COMMA
    end
    collector = visit v, collector
  end
  collector << ')'
  collector
end

#visit_ArelExtensions_Nodes_JsonSet(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 529

def visit_ArelExtensions_Nodes_JsonSet o,collector
  collector << 'JSON_SET('
  collector = visit o.dict, collector
  collector << COMMA
  if o.key.is_a?(Integer)
    collector << "\"$[#{o.key}]\""
  else
    collector = visit Arel::Nodes.build_quoted('$.')+o.key, collector
  end
  collector << COMMA
  collector = visit o.value, collector
  collector << ')'
  collector
end

#visit_ArelExtensions_Nodes_Log10(o, collector) ⇒ Object

Math functions



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# File 'lib/arel_extensions/visitors/mysql.rb', line 18

def visit_ArelExtensions_Nodes_Log10 o, collector
    collector << "LOG10("
    o.expressions.each_with_index { |arg, i|
      collector << Arel::Visitors::ToSql::COMMA if i != 0
      collector = visit arg, collector
    }
    collector << ")"
    collector
end

#visit_ArelExtensions_Nodes_Ltrim(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 172

def visit_ArelExtensions_Nodes_Ltrim o, collector
    collector << 'TRIM(LEADING '
    collector = visit o.right, collector
    collector << " FROM "
    collector = visit o.left, collector
    collector << ")"
    collector
end

#visit_ArelExtensions_Nodes_Power(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 28

def visit_ArelExtensions_Nodes_Power o, collector
  collector << "POW("
  o.expressions.each_with_index { |arg, i|
    collector << Arel::Visitors::ToSql::COMMA if i != 0
    collector = visit arg, collector
  }
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_RegexpReplace(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 200

def visit_ArelExtensions_Nodes_RegexpReplace o, collector
  if !regexp_replace_supported?
    warn("Warning : ArelExtensions: REGEXP_REPLACE does not seem to be available in the current version of the DBMS, it might crash")
  end
  super(o,collector)
end

#visit_ArelExtensions_Nodes_Repeat(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 190

def visit_ArelExtensions_Nodes_Repeat o, collector
  collector << "REPEAT("
  o.expressions.each_with_index { |arg, i|
    collector << Arel::Visitors::ToSql::COMMA if i != 0
    collector = visit arg, collector
  }
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_Rtrim(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 181

def visit_ArelExtensions_Nodes_Rtrim o, collector
  collector << 'TRIM(TRAILING '
  collector = visit o.right, collector
  collector << " FROM "
  collector = visit o.left, collector
  collector << ")"
  collector
end

#visit_ArelExtensions_Nodes_SMatches(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 77

def visit_ArelExtensions_Nodes_SMatches o, collector
    collector = visit o.left.collate, collector
    collector << ' LIKE '
    collector = visit o.right.collate, collector
    if o.escape
      collector << ' ESCAPE '
      visit o.escape, collector
    else
      collector
    end
end

#visit_ArelExtensions_Nodes_Std(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 431

def visit_ArelExtensions_Nodes_Std o, collector
  collector << (o.unbiased_estimator ? "STDDEV_SAMP(" : "STDDEV_POP(")
  visit o.left, collector
  collector << ")"
  visit_Aggregate_For_AggregateFunction o, collector
  collector
end

#visit_ArelExtensions_Nodes_Trim(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 163

def visit_ArelExtensions_Nodes_Trim o, collector
    collector << 'TRIM(' # BOTH
    collector = visit o.right, collector
    collector << " FROM "
    collector = visit o.left, collector
    collector << ")"
    collector
end

#visit_ArelExtensions_Nodes_Variance(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 439

def visit_ArelExtensions_Nodes_Variance o, collector
  collector << (o.unbiased_estimator ? "VAR_SAMP(" : "VAR_POP(")
  visit o.left, collector
  collector << ")"
  visit_Aggregate_For_AggregateFunction o, collector
  collector
end

#visit_ArelExtensions_Nodes_Wday(o, collector) ⇒ Object 



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# File 'lib/arel_extensions/visitors/mysql.rb', line 310

def visit_ArelExtensions_Nodes_Wday o, collector
  collector << "(WEEKDAY("
  collector = visit o.date, collector
  collector << ") + 1) % 7"
  collector
end

#window_supported? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arel_extensions/visitors/mysql.rb', line 452

def window_supported?
  version_supported?('10.2.3', '8.0')
end