module Sequel::Postgres::DatasetMethods

# File lib/sequel/adapters/shared/postgres.rb, line 1138
def analyze
  explain(:analyze=>true)
end

# File lib/sequel/adapters/shared/postgres.rb, line 1145
def complex_expression_sql_append(sql, op, args)
  case op
  when :^
    j = XOR_OP
    c = false
    args.each do |a|
      sql << j if c
      literal_append(sql, a)
      c ||= true
    end
  when :ILIKE, :'NOT ILIKE'
    sql << PAREN_OPEN
    literal_append(sql, args.at(0))
    sql << SPACE << op.to_s << SPACE
    literal_append(sql, args.at(1))
    sql << ESCAPE
    literal_append(sql, BACKSLASH)
    sql << PAREN_CLOSE
  else
    super
  end
end

# File lib/sequel/adapters/shared/postgres.rb, line 1169
def explain(opts=OPTS)
  with_sql((opts[:analyze] ? EXPLAIN_ANALYZE : EXPLAIN) + select_sql).map(QUERY_PLAN).join(CRLF)
end

# File lib/sequel/adapters/shared/postgres.rb, line 1174
def for_share
  lock_style(:share)
end

# File lib/sequel/adapters/shared/postgres.rb, line 1180
def full_text_search(cols, terms, opts = OPTS)
  lang = opts[:language] || 'simple'
  terms = terms.join(' | ') if terms.is_a?(Array)
  filter("to_tsvector(?::regconfig, ?) @@ to_tsquery(?::regconfig, ?)", lang, full_text_string_join(cols), lang, terms)
end

# File lib/sequel/adapters/shared/postgres.rb, line 1187
def insert(*values)
  if @opts[:returning]
    # already know which columns to return, let the standard code
    # handle it
    super
  elsif @opts[:sql]
    # raw SQL used, so don't know which table is being inserted
    # into, and therefore can't determine primary key.  Run the
    # insert statement and return nil.
    super
    nil
  else
    # Force the use of RETURNING with the primary key value.
    returning(insert_pk).insert(*values){|r| return r.values.first}
  end
end

# File lib/sequel/adapters/shared/postgres.rb, line 1205
def insert_select(*values)
  returning.insert(*values){|r| return r}
end

# File lib/sequel/adapters/shared/postgres.rb, line 1214
def lock(mode, opts=OPTS)
  if block_given? # perform locking inside a transaction and yield to block
    @db.transaction(opts){lock(mode, opts); yield}
  else
    sql = 'LOCK TABLE '
    source_list_append(sql, @opts[:from])
    mode = mode.to_s.upcase.strip
    unless LOCK_MODES.include?(mode)
      raise Error, "Unsupported lock mode: #{mode}"
    end
    sql << " IN #{mode} MODE"
    @db.execute(sql, opts)
  end
  nil
end

# File lib/sequel/adapters/shared/postgres.rb, line 1231
def multi_insert_sql(columns, values)
  sql = LiteralString.new('VALUES ')
  expression_list_append(sql, values.map{|r| Array(r)})
  [insert_sql(columns, sql)]
end

# File lib/sequel/adapters/shared/postgres.rb, line 1239
def supports_cte_in_subqueries?
  supports_cte?
end

# File lib/sequel/adapters/shared/postgres.rb, line 1244
def supports_distinct_on?
  true
end

# File lib/sequel/adapters/shared/postgres.rb, line 1249
def supports_lateral_subqueries?
  server_version >= 90300
end

# File lib/sequel/adapters/shared/postgres.rb, line 1254
def supports_modifying_joins?
  true
end

# File lib/sequel/adapters/shared/postgres.rb, line 1264
def supports_regexp?
  true
end

# File lib/sequel/adapters/shared/postgres.rb, line 1259
def supports_returning?(type)
  true
end

# File lib/sequel/adapters/shared/postgres.rb, line 1269
def supports_timestamp_timezones?
  true
end

# File lib/sequel/adapters/shared/postgres.rb, line 1274
def supports_window_functions?
  server_version >= 80400
end

# File lib/sequel/adapters/shared/postgres.rb, line 1293
def truncate(opts = OPTS)
  if opts.empty?
    super()
  else
    clone(:truncate_opts=>opts).truncate
  end
end

# File lib/sequel/adapters/shared/postgres.rb, line 1302
def window(name, opts)
  clone(:window=>(@opts[:window]||[]) + [[name, SQL::Window.new(opts)]])
end