slightly reworked LoD hierarchy query to improve performance

3dcitydb · Jul 13, 2024 · 897097a · 897097a
1 parent c25bd89
commit 897097a
Showing 1 changed file with 22 additions and 17 deletions.
diff --git a/citydb-database-postgres/src/main/java/org/citydb/database/postgres/SchemaAdapter.java b/citydb-database-postgres/src/main/java/org/citydb/database/postgres/SchemaAdapter.java
@@ -29,13 +29,11 @@
 import org.citydb.model.common.RelationType;
 import org.citydb.sqlbuilder.common.SqlObject;
 import org.citydb.sqlbuilder.function.Function;
-import org.citydb.sqlbuilder.join.Joins;
 import org.citydb.sqlbuilder.literal.BooleanLiteral;
 import org.citydb.sqlbuilder.literal.IntegerLiteral;
 import org.citydb.sqlbuilder.literal.StringLiteral;
 import org.citydb.sqlbuilder.operation.Case;
 import org.citydb.sqlbuilder.operation.Not;
-import org.citydb.sqlbuilder.operation.Operators;
 import org.citydb.sqlbuilder.query.CommonTableExpression;
 import org.citydb.sqlbuilder.query.Select;
 import org.citydb.sqlbuilder.schema.Table;
@@ -123,20 +121,21 @@ public Select getRecursiveLodQuery(Set<String> lods, boolean requireAll, int sea
                 adapter.getConnectionDetails().getSchema(), generator);
 
         Select featureQuery = Select.newInstance()
-                .select(PlainText.of("null::bigint").as("id"),
-                        table.column("id").as("feature_id"),
+                .select(table.column("id").as("feature_id"),
                         table.column("id").as("val_feature_id"),
-                        IntegerLiteral.of(RelationType.CONTAINS.getDatabaseValue()).as("val_relation_type"),
-                        PlainText.of("null::text").as("val_lod"));
+                        IntegerLiteral.of(0).as("val_relation_type"));
         Select propertyQuery = Select.newInstance()
-                .select(property.column("id"),
-                        property.column("feature_id"),
+                .select(property.column("feature_id"),
                         property.column("val_feature_id"),
-                        property.column("val_relation_type"),
-                        property.column("val_lod"))
+                        property.column("val_relation_type"))
                 .from(property)
-                .join(Joins.inner(hierarchy, "val_feature_id", Operators.EQUAL_TO, property.column("feature_id"))
-                        .condition(hierarchy.column("val_relation_type").eq(RelationType.CONTAINS.getDatabaseValue())));
+                .join(hierarchy).on(hierarchy.column("val_feature_id").eq(property.column("feature_id")))
+                .where(property.column("val_feature_id").isNotNull(),
+                        property.column("val_relation_type").eq(RelationType.CONTAINS.getDatabaseValue()));
+        Select hierarchyQuery = Select.newInstance()
+                .withRecursive(CommonTableExpression.of(hierarchy.getName(), featureQuery.unionAll(propertyQuery)))
+                .select(hierarchy.column("val_feature_id"))
+                .from(hierarchy);
 
         if (searchDepth >= 0 && searchDepth != Integer.MAX_VALUE) {
             featureQuery.select(IntegerLiteral.of(0).as("depth"));
@@ -145,6 +144,7 @@ public Select getRecursiveLodQuery(Set<String> lods, boolean requireAll, int sea
                             .then(PlainText.of("depth"))
                             .orElse(PlainText.of("depth").plus(1)))
                     .where(PlainText.of("depth").lt(IntegerLiteral.of(searchDepth + 1)));
+            hierarchyQuery.where(PlainText.of("depth").lt(IntegerLiteral.of(searchDepth + 1)));
         } else {
             featureQuery.select(BooleanLiteral.FALSE.as("is_cycle"),
                     PlainText.of("array[]::bigint[]").as("path"));
@@ -153,20 +153,25 @@ public Select getRecursiveLodQuery(Set<String> lods, boolean requireAll, int sea
                     .where(Not.of(PlainText.of("is_cycle")));
         }
 
+        hierarchy = Table.of(hierarchyQuery, generator);
+        property = Table.of(org.citydb.database.schema.Table.PROPERTY.getName(),
+                adapter.getConnectionDetails().getSchema(), generator);
+
         Select select = Select.newInstance()
-                .withRecursive(CommonTableExpression.of(hierarchy.getName(), featureQuery.unionAll(propertyQuery)))
                 .select(IntegerLiteral.of(1))
-                .from(hierarchy);
+                .from(property)
+                .join(hierarchy).on(hierarchy.column("val_feature_id").eq(property.column("feature_id")))
+                .fetch(1);
 
         if (!lods.isEmpty()) {
             select.where(adapter.getSchemaAdapter().getOperationHelper()
-                    .in(hierarchy.column("val_lod"), lods.stream().map(StringLiteral::of).toList()));
+                    .in(property.column("val_lod"), lods.stream().map(StringLiteral::of).toList()));
             if (requireAll && lods.size() > 1) {
-                select.having(Function.of("count", hierarchy.column("val_lod")).qualifier("distinct")
+                select.having(Function.of("count", property.column("val_lod")).qualifier("distinct")
                         .eq(lods.size()));
             }
         } else {
-            select.where(hierarchy.column("val_lod").isNotNull());
+            select.where(property.column("val_lod").isNotNull());
         }
 
         return select;