Class: BazaModels::Query::SqlGenerator

Inherits:
Object
  • Object
show all
Defined in:
lib/baza_models/query/sql_generator.rb

Instance Method Summary collapse

Constructor Details

#initialize(args) ⇒ SqlGenerator

Returns a new instance of SqlGenerator.



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# File 'lib/baza_models/query/sql_generator.rb', line 2

def initialize(args)
  @query = args.fetch(:query)

  instance_variables = [:db, :selects, :joins, :wheres, :groups, :orders, :per, :limit, :offset, :model, :table_name, :reverse_order]
  instance_variables.each do |instance_variable|
    value = @query.instance_variable_get(:"@#{instance_variable}")
    instance_variable_set(:"@#{instance_variable}", value)
  end
end

Instance Method Details

#to_sql ⇒ Object 



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# File 'lib/baza_models/query/sql_generator.rb', line 12

def to_sql
  sql = "SELECT "

  if @selects.empty?
    sql << "#{@db.sep_table}#{@model.table_name}#{@db.sep_table}.*"
  else
    sql << @selects.join(", ")
  end

  sql << " FROM #{@db.sep_table}#{@model.table_name}#{@db.sep_table}"

  unless @joins.empty?
    @joins.each do |join|
      sql << " #{join}"
    end
  end

  unless @wheres.empty?
    sql << " WHERE "

    first = true
    @wheres.each do |where|
      if first == true
        first = false
      else
        sql << " AND "
      end

      sql << where
    end
  end

  unless @groups.empty?
    sql << " GROUP BY "

    first = true
    @groups.each do |group|
      if first
        first = false
      else
        sql << ", "
      end

      sql << group
    end
  end

  unless @orders.empty?
    sql << " ORDER BY "

    first = true
    @orders.each do |order|
      if first
        first = false
      else
        sql << ", "
      end

      if @reverse_order
        if order =~ /\s+desc/i
          order = order.gsub(/\s+desc/i, " ASC")
        elsif order =~ /\s+asc/i
          order = order.gsub(/\s+asc/i, " DESC")
        else
          order = "#{order} DESC"
        end
      end

      sql << order
    end
  end

  if @limit && @offset
    sql << " LIMIT #{@offset.to_i}, #{@limit.to_i}"
  elsif @limit
    sql << " LIMIT #{@limit.to_i}"
  end

  sql.strip
end