How to specify multiple style file with osm2pgsql query

I have imported entire planet data using the following query.

sudo osm2pgsql --drop --hstore --slim -r pbf -C 32000 --flat-nodes node.cache --number-processes 8 -d gis -U root /mnt/data/planetdata/planet-latest.osm.pbf

But whenever I am testing rendered using-

renderd -f -c /usr/local/etc/renderd.conf

It is logging the following errors-

renderd[17978]: An error occurred while loading the map layer 'osm': Postgis Plugin: ERROR:  COALESCE types text and integer cannot be matched
LINE 18:   ORDER BY COALESCE(layer,0), way_area DESC
                               ^
in executeQuery Full sql was: 'SELECT * FROM (SELECT
way,
"natural",
waterway,
landuse,
name,
way_area/NULLIF(0::real*0::real,0) AS way_pixels,
CASE WHEN tags->'intermittent' IN ('yes')
  OR tags->'seasonal' IN ('yes', 'spring', 'summer', 'autumn', 'winter', 'wet_season', 'dry_season')
  THEN 'yes' ELSE 'no' END AS int_intermittent
FROM planet_osm_polygon
WHERE
(waterway IN ('dock', 'riverbank')
  OR landuse IN ('reservoir', 'basin')
  OR "natural" IN ('water', 'glacier'))
AND building IS NULL
AND way_area > 1*0::real*0::real
ORDER BY COALESCE(layer,0), way_area DESC
) AS water_areas LIMIT 0'
encountered during parsing of layer 'water-areas' in Layer at line 8298 of 
'/mnt/data/styles/osm/openstreetmap-carto-master/osm.xml'
debug: init_storage_backend: initialising file storage backend at: /var/lib/mod_tile
renderd[17978]: Loading parameterization function for 
renderd[17978]: An error occurred while loading the map layer 'osm': Postgis Plugin: ERROR:  COALESCE 
types text and integer cannot be matched
LINE 18:   ORDER BY COALESCE(layer,0), way_area DESC
                               ^
in executeQuery Full sql was: 'SELECT * FROM (SELECT
way,
"natural",
waterway,
landuse,
name,
way_area/NULLIF(0::real*0::real,0) AS way_pixels,
CASE WHEN tags->'intermittent' IN ('yes')
  OR tags->'seasonal' IN ('yes', 'spring', 'summer', 'autumn', 'winter', 'wet_season', 'dry_season')
  THEN 'yes' ELSE 'no' END AS int_intermittent
FROM planet_osm_polygon
WHERE
(waterway IN ('dock', 'riverbank')
  OR landuse IN ('reservoir', 'basin')
  OR "natural" IN ('water', 'glacier'))
AND building IS NULL
AND way_area > 1*0::real*0::real
ORDER BY COALESCE(layer,0), way_area DESC
) AS water_areas LIMIT 0'
encountered during parsing of layer 'water-areas' in Layer at line 8298 of 
'/mnt/data/styles/osm/openstreetmap-carto-master/osm.xml'

When I googled for this error.I found a this link referencing the same issue- link

But I am using style from openstreetmap-carto-master and mapbox-carto(osm-bright) both.

openstreetmap-carto-master - link

mapbox-carto - link

So, In my case how can I specify two style file in my query? Or How can I solve this issue?

If anyone have solved this issue ,please let me know.