Adding source_ids column if not exists. (#1600)

Adding source_ids column if not exist in the table 
 - osm_transportation_merge_linestring_gen_z11
 - osm_transportation_merge_linestring_gen_z8
 - osm_transportation_name_linestring
 - osm_important_waterway_linestring

layers/transportation/update_transportation_merge.sql

@@ -144,6 +144,8 @@ CREATE TABLE IF NOT EXISTS osm_transportation_merge_linestring_gen_z11(
     layer integer
 );
 
+ALTER TABLE osm_transportation_merge_linestring_gen_z11 ADD COLUMN IF NOT EXISTS source_ids bigint[];
+
 -- Create osm_transportation_merge_linestring_gen_z10 as a copy of osm_transportation_merge_linestring_gen_z11 but
 -- drop the "source_ids" column. This can be done because z10 and z9 tables are only simplified and not merged,
 -- therefore relations to sources are direct via the id column.
@@ -459,6 +461,8 @@ CREATE TABLE IF NOT EXISTS osm_transportation_merge_linestring_gen_z8(
     z_order integer
 );
 
+ALTER TABLE osm_transportation_merge_linestring_gen_z8 ADD COLUMN IF NOT EXISTS source_ids bigint[];
+
 -- Create osm_transportation_merge_linestring_gen_z7 as a copy of osm_transportation_merge_linestring_gen_z8 but
 -- drop the "source_ids" column. This can be done because z7 to z5 tables are only simplified and not merged,
 -- therefore relations to sources are direct via the id column.