PostgreSQL query using GROUP BY question
Hiking & ActivitiesHow to use group by clause in PostgreSQL? The PostgreSQL GROUP BY condition is used with SELECT command, and it can also be used to reduce the redundancy in the result.The basic syntax of the GROUP BY clause is as follows: SELECT column-list. FROM table_name. WHERE [conditions ] GROUP BY column1, column2…. columnN. ORDER BY
What causes wrong placement of JPGs in QGIS 2.8.1?
Hiking & ActivitiesHow do I georeference a JPEG in QGIS? To georeference the map: Open the georeference tool, Raster ‣ Georeferencer ‣ Georeferencer. Add the map image file, rautjarvi_map. When prompted find and select the KKJ / Finland zone 2 CRS, it is the CRS that was used in Finland back in 1994 when this map was
Shapefile and multiple lines of census data QGIS
Hiking & ActivitiesHow do I add population data in QGIS? Calculate the Population Density Right click the “SubPlace” layer in the TOC’ Select “Open attribute table” Toggle editing mode by click the button with a pencil. Click the “Create a new column” button. Name the new column “POPDENS” For “Type” select “Decimal number” Set the width to
Finding the side of a square that a point intersects with R (sp)
Hiking & ActivitiesHow do you find the point of intersection of a square? So we can find the point or points of intersection by solving the equation f(x) = g(x). The solution of this equation will give us the x value(s) of the point(s) of intersection. We can then find the y value by putting the value
Polygon Layer Cleaning with QGIS
Hiking & ActivitiesHow do I clean a polygon in QGIS? Clean Topology Error in Polygon Data set Open v. clean. To clean the error, there are three processes are needed to be done: break polygon, remove duplicate and remove area. In the third step we must define threshold value. Leave the other parameter as default. Click Run
How to add Raster legends in QGIS map composer?
Hiking & ActivitiesCan you add a legend in Qgis? Use the [Add group] button to add a legend group. Use the [plus] and [minus] button to add or remove layers. The [Edit] button is used to edit the layer, groupname or title. First you need to select the legend item. How do I change the legend on