You need to reload the data.
You need to create new PostgreSQL Enterprise Geodatabases on premises then change the default geometry type in the sde.dbtune ##defaults from st_geometry to postgis and reload the data using ArcCatalog or ArcGIS Pro.
Note, if you have traditional versioning or branch versioning on the old st_geometry geodatabases then you need to post/reconcile all child versions with the sde.default version, then delete the versions and execute a geodatabase sde compress (if traditional versioning), then perform the PostgreSQL maintenance to gather new statistics and then proceed to reload the data.
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sde dbtune configuration keywords
https://pro.arcgis.com/en/pro-app/latest/help/data/geodatabases/overview/configuration-keywords-for-...
Export Geodatabase Configuration Keyword
modify the dbtune export file and save
from:
##DEFAULTS
GEOMETRY_STORAGE "ST_GEOMETRY"
to:
##DEFAULTS
GEOMETRY_STORAGE "PG_GEOMETRY"
Import Geodatabase Configuration Keyword
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Create New Geodatabase PostgreSQL
https://pro.arcgis.com/en/pro-app/latest/help/data/geodatabases/manage-postgresql/setup-geodatabase-...
11. Use the Spatial Type drop-down list to choose the spatial type the geodatabase will use: either ST_Geometry or PostGIS.
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| Marcelo Marques | Principal Product Engineer | Esri |
| Cloud & Database Administrator | OCP - Oracle Certified Professional |
I work with Enterprise Geodatabases since 1997.
“ I do not fear computers. I fear the lack of them." Isaac Isimov