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3 votes
Accepted

Adding parcel number to site when there are many sites in QGIS

I'm not sure I completely understand your question, but [add autoincremental field] in the qgis toolbox may be able to help you. It can take all fields with a specific value and assign numbers to each ...
5 votes

Adding parcel number to site when there are many sites in QGIS

You can use row_number and partition by site: --Create a test table drop table if exists public.test; create table public.test (id serial, siteid varchar(10)); insert into public.test (siteid) values ...
  • 61.1k
0 votes

Performing ST_Distance query in file geodatabase using ArcGIS Pro

Although the existing answer and comments still stand, i.e., not possible with file geodatabases, it is worth pointing out this is possible with mobile geodatabases. As support for mobile ...
  • 1,658
3 votes
Accepted

PostGIS subquery error when trying to randomly distribute points in polygons

Technically, @RainForest's solution directly adresses the error you are seeing; you are SETing a single column so the respective expression (here the sub-query) must return a single value (here the ...
  • 27.1k
2 votes

PostGIS subquery error when trying to randomly distribute points in polygons

Just delete pt.*, from subquery SELECT ST_GeneratePoints(lsd.geom, 1, floor(random() * 5000 + 1)::int) FROM public.unjoined_pts2 AS pt, public.grid_concave_hull AS lsd WHERE ...
4 votes

QGIS, Rule-Based Symbology Not Working, But Feature Filter Does

Short answer: Rule based styling expressions are not SQL, use the expression syntax instead
  • 2,777
4 votes

QGIS - Countif function on columns

You can aggregate the values in an array, filter all elements greater than 0 and then get the length of the filtered array: Use this expression in the field calculator on the layer itself: ...
  • 12.2k
5 votes

I need to expect multi value with if statement

You need to replace ' and' with ''. E.g. Ahmed and Marten -> Ahmed Marten, and then check replaced_name is title(replaced_name). Use this expression: with_variable( 'text', -- variable name ...
0 votes

I need to expect multi value with if statement

I don't know if I understand your question correctly. But try something like: if( strpos( 'the name you are searching for' , "name" ) > 0 , 'yes' , 'no' )
8 votes
Accepted

Using eval function in Virtual Layer in QGIS

This is an interesting question that has piqued my interest. As I'm working in QGIS Windows, I set SPATIALITE_SECURITY=relaxed in the global Windows environment. After many trials and errors, I found ...
  • 4,651
1 vote

Is it possible to make a condition for a field in QGIS using CSV

So I understand that Table 2 already contains the num and obey fields? If so, you can just perform a Table Join using the Join attributes by field value from the Processing algorithm Toolbox. A ...
7 votes
Accepted

Creating virtual layer with extent of features from multiple layers in QGIS

Use this query, where in the last line, replace id with the attribute name that should have the same value and replace poly and lines with the names of your layers: SELECT bounds(st_union(g1....
  • 55.3k
2 votes

GeoJSON from SQL View

You seem to have a logical misconception in your approach, leading to the syntax issue: you are sending a FeatureCollection to the server to eventually get passed into the query - however, ...
  • 27.1k
0 votes

GeoJSON from SQL View

NB: This answer was for an earlier edition of the question which was using GET rather than POST. Therefore this answer is no longer relevant, due to edits to the question. OPTION 1 Use an HTTP POST ...
6 votes
Accepted

QGIS does not find existing column when drawing lines between two point layers

You miss the aliases for the layer names (q and z) and the points in the column names are interfering with the layer.column syntax. Try this: select q."q.id", z."z.id", makeline(q....
  • 12.2k
10 votes
Accepted

QGIS - Countif function

This expression gives you what you need: with_variable( 'ar', array(Attribute1, Attribute2, Attribute3, Attribute4), array_length(@ar) - array_count(@ar, 0) ) with_variable assigns the second ...
1 vote

PostGIS - Reading geometry from a shapefile directly in the SQL query

With foreign data wrappers https://wiki.postgresql.org/wiki/Foreign_data_wrappers#Geo_Wrappers, yes. However, creating a fdw for a shapefile https://www.crunchydata.com/blog/querying-spatial-data-with-...
  • 59k

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