diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9997cd81461632727647bab467779089789dfb93..ea88e321261634711f9e084f318adf497672d66c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
### Changed
+* Select queries would originally only select the returned properties by their
+ names and would not check if a property is a subtype of a selected property. This
+ has changed now and select queries will also return subtypes of selected
+ properties.
+
### Deprecated
* `SERVER_SIDE_SCRIPTING_BIN_DIR` property is deprecated.
diff --git a/src/doc/CaosDB-Query-Language.md b/src/doc/CaosDB-Query-Language.md
index 47a890d716564eb72c70de4f9d39d1cd00d92157..07fbdbc310b8d22de4642f041918710e6e707488 100644
--- a/src/doc/CaosDB-Query-Language.md
+++ b/src/doc/CaosDB-Query-Language.md
@@ -351,6 +351,33 @@ Any result set can be filtered by logically combining POV filters or back refere
* REFERENCE:: This one is tricky: `REFERENCE TO` expresses a the state of _having_ a reference property. `REFERENCED BY` expresses the state of _being_ referenced by another entity.
* COUNT:: `COUNT` works like `FIND` but doesn't return the entities.
+
+## Select Queries
+
+In contrast to `FIND` queries, which always return the complete entity, there are `SELECT` queries which only return the entity with only those properties which are specified in the query. The syntax is very similar to `FIND` queries - just replace the `FIND` by `SELECT <comma separated list of selectors> FROM`:
+
+`SELECT p1, p2, p3 FROM Record ename`
+
+However, the `SELECT` query can also return properties of referenced entities and thereby are a means of joining entities together and return a custom view or projection:
+
+`SELECT Conductor.Last Name FROM Experiment`
+
+would return the conductor's last name, when `Conductor` is a reference property of `Experiment` and `Last Name` is a property of the `Conductor` records.
+
+### Selectors
+
+Selectors are strings of entity names which are separated by `.` (dot). E.g. `Conductor.Last Name` or `Conductor.Address` or even `Experiment.Conductor.Last name`. Selectors in a `SELECT` queries are separated by `,` (comma). E.g. `Conductor.First Name, Conductor.Last Name`.
+
+### Evaluation of Selectors
+
+The query will return all those properties which have the same name as
+specified by the selector (case-insensitive). However, `SELECT` queries are
+also capable of subtyping in the selectors:
+
+`SELECT Person FROM Experiment` would return all `Person` properties but all `Conductors` as well, if `Conductor` is a child of `Person`.
+
+Note: When a property `responsible` with data type `Person` exists, the above `SELECT` statement would not include records that use this property (since `responsible` is not a child of Person).
+
## Versioning
Since Caosdb 0.2 entities are optionally version controlled. The query language will be extended to include versioning in the future. A current minimal implementation introduces the `ANY VERSION OF` modifier which can be used to return all matching versions in the results of `COUNT`, `FIND`, and `SELECT` queries.
diff --git a/src/main/java/org/caosdb/server/database/backend/transaction/IsSubType.java b/src/main/java/org/caosdb/server/database/backend/transaction/IsSubType.java
index d75fb2c2453613c50915678d81f53f696589afd4..683903f396a186c8243b6bba20c0d19e29a61688 100644
--- a/src/main/java/org/caosdb/server/database/backend/transaction/IsSubType.java
+++ b/src/main/java/org/caosdb/server/database/backend/transaction/IsSubType.java
@@ -29,19 +29,36 @@ import org.caosdb.server.database.exceptions.TransactionException;
public class IsSubType extends BackendTransaction {
private final Integer child;
- private final Integer parent;
+ private Integer parent = null;
+ private String parentName = null;
public IsSubType(final Integer child, final Integer parent) {
this.child = child;
this.parent = parent;
}
- private boolean isSubType;
+ public IsSubType(Integer child, String parent) {
+ this.parentName = parent;
+ this.child = child;
+ }
+
+ private Boolean isSubType = null;
@Override
public void execute() throws TransactionException {
final IsSubTypeImpl t = getImplementation(IsSubTypeImpl.class);
- this.isSubType = t.execute(this.child, this.parent);
+
+ if (this.parent == null) {
+ this.isSubType = false;
+ for (Integer parent : execute(new GetIDByName(parentName, false)).getList()) {
+ this.isSubType = t.execute(this.child, parent);
+ if (this.isSubType) {
+ return;
+ }
+ }
+ } else {
+ this.isSubType = t.execute(this.child, this.parent);
+ }
}
public boolean isSubType() {
diff --git a/src/main/java/org/caosdb/server/database/backend/transaction/RetrieveFullEntity.java b/src/main/java/org/caosdb/server/database/backend/transaction/RetrieveFullEntity.java
index 38cd7073613e6477d013f8923aaecfc188a3c234..f9b6356adfcbe42760f272c4540c25489d060446 100644
--- a/src/main/java/org/caosdb/server/database/backend/transaction/RetrieveFullEntity.java
+++ b/src/main/java/org/caosdb/server/database/backend/transaction/RetrieveFullEntity.java
@@ -1,24 +1,20 @@
/*
- * ** header v3.0
- * This file is a part of the CaosDB Project.
+ * ** header v3.0 This file is a part of the CaosDB Project.
*
- * Copyright (C) 2018 Research Group Biomedical Physics,
- * Max-Planck-Institute for Dynamics and Self-Organization Göttingen
- * Copyright (C) 2020 Timm Fitschen <t.fitschen@indiscale.com>
- * Copyright (C) 2020 IndiScale GmbH <info@indiscale.com>
+ * Copyright (C) 2018 Research Group Biomedical Physics, Max-Planck-Institute for Dynamics and
+ * Self-Organization Göttingen Copyright (C) 2020 Timm Fitschen <t.fitschen@indiscale.com> Copyright
+ * (C) 2020 IndiScale GmbH <info@indiscale.com>
*
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
+ * This program is free software: you can redistribute it and/or modify it under the terms of the
+ * GNU Affero General Public License as published by the Free Software Foundation, either version 3
+ * of the License, or (at your option) any later version.
*
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU Affero General Public License for more details.
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
+ * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
*
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ * You should have received a copy of the GNU Affero General Public License along with this program.
+ * If not, see <https://www.gnu.org/licenses/>.
*
* ** end header
*/
@@ -27,6 +23,7 @@ package org.caosdb.server.database.backend.transaction;
import java.util.LinkedList;
import java.util.List;
import org.caosdb.server.database.BackendTransaction;
+import org.caosdb.server.database.exceptions.EntityDoesNotExistException;
import org.caosdb.server.datatype.ReferenceDatatype;
import org.caosdb.server.datatype.ReferenceValue;
import org.caosdb.server.entity.EntityInterface;
@@ -124,10 +121,9 @@ public class RetrieveFullEntity extends BackendTransaction {
*/
public void retrieveSubEntities(EntityInterface e, List<Selection> selections) {
for (final Selection s : selections) {
+ String propertyName = s.getSelector();
if (s.getSubselection() != null) {
- String propertyName = s.getSelector();
-
// Find matching (i.e. referencing) Properties
for (Property p : e.getProperties()) {
// get reference properties by name.
@@ -142,10 +138,47 @@ public class RetrieveFullEntity extends BackendTransaction {
ReferenceValue value = (ReferenceValue) p.getValue();
RetrieveEntity ref = new RetrieveEntity(value.getId());
- // recursion! (Only for the matching selections)
+ // recursion! (Only for the matching selections)
retrieveFullEntity(ref, getSubSelects(selections, propertyName));
value.setEntity(ref, true);
}
+ continue;
+ }
+ try {
+ boolean isSubtype = execute(new IsSubType(p.getId(), propertyName)).isSubType();
+ if (isSubtype) {
+ if (p.getValue() != null) {
+ if (p.getDatatype() instanceof ReferenceDatatype) {
+ try {
+ p.parseValue();
+ } catch (Message m) {
+ p.addError(m);
+ }
+
+ ReferenceValue value = (ReferenceValue) p.getValue();
+ RetrieveEntity ref = new RetrieveEntity(value.getId());
+ // recursion! (Only for the matching selections)
+ retrieveFullEntity(ref, getSubSelects(selections, propertyName));
+ value.setEntity(ref, true);
+ p.setName(propertyName);
+ }
+ }
+ }
+ } catch (EntityDoesNotExistException exc) {
+ // unknown parent name.
+ }
+ }
+ } else {
+ for (Property p : e.getProperties()) {
+ if (!propertyName.equalsIgnoreCase(p.getName())) {
+ try {
+ boolean isSubtype = execute(new IsSubType(p.getId(), propertyName)).isSubType();
+ if (isSubtype) {
+ p.setName(propertyName);
+ }
+ } catch (EntityDoesNotExistException exc) {
+ // unknown parent name.
+ }
}
}
}
diff --git a/src/main/java/org/caosdb/server/jobs/Job.java b/src/main/java/org/caosdb/server/jobs/Job.java
index b3bfda36bedbabfa3eac2eada3938c731041178d..5d8dd5d98a00960561c6b97f8e1f4fa118eafd0b 100644
--- a/src/main/java/org/caosdb/server/jobs/Job.java
+++ b/src/main/java/org/caosdb/server/jobs/Job.java
@@ -57,12 +57,10 @@ import org.caosdb.server.utils.Observer;
import org.caosdb.server.utils.ServerMessages;
import org.reflections.Reflections;
-
/**
* This is a Job.
*
* @todo Describe me.
- *
*/
public abstract class Job extends AbstractObservable implements Observer {
private Transaction<? extends TransactionContainer> transaction = null;