find coords per quadrant per iso code (depending on center)

SQL

set @ns:=0;
#use commonswiki_p;set @ns:=6;
set @iso1:='VN';
#set @iso2:='' or code
set @iso2:='60';
/*
  'XA', 'XI', 'XN', 'XO', 'XP', 'XS', 
  'AE','AF','AX','AL','AS','AD','AO','AI','AQ','AG','AR','AM','AW','AU','AT','AZ',
  'BS','BH','BD','BB','BL','BY','BE','BZ','BJ','BM','BT','BO','BQ','BA','BW','BV','BR','BN','BG','BF','BI',
  'CM','CA','CH','CV','CF','CL','CN','CX','CC','CO','CG','CD','CK','CR','CI','CU','CW','CY','CZ',
  'DE','DK','DJ','DM','DO','DZ',
  'EC','EG','EH','ER','EE','ES','ET',
  'FK','FO','FJ','FI','FR','FX',
  'GA','GB','GM','GE','GF','GH','GI','GR','GL','GD','GP','GU','GS','GT','GG','GN','GQ','GW','GY',
  'HT','HM','HN','HK','HR','HU',
  'IS','IN','IO','ID','IR','IQ','IE','IM','IL','IT',
  'JM','JP','JE','JO','KZ','KE','KH','KI','KM','KN','KP','KR','KW','KG','KY',
  'LA','LB','LC','LV','LK','LS','LR','LY','LI','LT','LU',
  'MO','MK','MF','MG','MW','MY','MV','ML','MT','MH','MQ','MR','MU','MX','FM','MD','MC','MN','ME','MS','MA','MZ','MM',
  'NA','NR','NP','NL','NC','NZ','NI','NE','NG','NU','NF','MP','NO','OM',
  'PK','PW','PS','PA','PF','PG','PY','PE','PH','PM','PN','PL','PT','PR','QA',
  'RE','RO','RU','RW','RS',
  'SM','ST','SA','SH','SN','SC','SL','SG','SX','SK','SI','SB','SO','SS','SD','SR','SJ','SZ','SE','SV','SY',
  'TD','TF','TW','TJ','TZ','TH','TL','TG','TK','TO','TT','TN','TR','TM','TC','TV',
  'UG','UA','US','UM','UY','UZ',
  'VA','VC','VU','VE','VN','VG','VI',
  'WF','WS','YE','YT','ZA','ZM','ZW'
*/

select distinct sqrt((gt_lat - cen_gt_lat)*(gt_lat - cen_gt_lat) + (gt_lon - cen_gt_lon)*(gt_lon - cen_gt_lon)) as distanz_ungefaehr, 
       gt_lat, gt_lon, gt_type, gt_page_id, gt_name,
       p1.page_namespace as ns,
       p1.page_title as title,
       gt_country,gt_region FROM geo_tags AS g1 JOIN page AS p1 ON g1.gt_page_id = p1.page_id,
       (select avg(gt_lat) cen_gt_lat,avg(gt_lon) cen_gt_lon,count(*) from geo_tags
        where 
        	case 
        		when @iso2=''
        		then gt_country=@iso1 and gt_region is null
        		else gt_country=@iso1 and gt_region=@iso2
        		end) as zentrumdavon
        where
        	case
            	when @iso2=''
                then gt_country=@iso1 and gt_region is null
                else gt_country=@iso1 and gt_region=@iso2
                end
            #and gt_lat > cen_gt_lat and gt_lon < cen_gt_lon
       #having ns= @ns
       order by 1 desc, title asc, gt_name asc limit 2000;
SQL

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