Modify Cassandra version_successor table

change item_id_set to a singular item_id

Author: seanlobo

app/dao/versions/cassandra/CassandraVersionHistoryDagFactory.java

@@ -15,25 +15,21 @@
 package dao.versions.cassandra;
 
 import com.google.common.base.CaseFormat;
-
 import dao.versions.VersionHistoryDagFactory;
 import db.CassandraClient;
-import db.CassandraResults;
-import db.DbClient;
 import db.DbDataContainer;
 import exceptions.GroundException;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
 import models.models.Structure;
 import models.versions.GroundType;
 import models.versions.Item;
 import models.versions.Version;
 import models.versions.VersionHistoryDag;
 import models.versions.VersionSuccessor;
 
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-
 public class CassandraVersionHistoryDagFactory implements VersionHistoryDagFactory {
   private final CassandraClient dbClient;
   private final CassandraVersionSuccessorFactory versionSuccessorFactory;
@@ -87,14 +83,11 @@ public void addEdge(VersionHistoryDag dag, long parentId, long childId, long ite
     VersionSuccessor successor = this.versionSuccessorFactory.create(parentId, childId);
 
     // Adding to the entry with id = successor.getId()
-    List<DbDataContainer> predicate = new ArrayList<>();
+    List<DbDataContainer> newValue = new ArrayList<>(), predicate = new ArrayList<>();
+    newValue.add(new DbDataContainer("item_id", GroundType.LONG, itemId));
     predicate.add(new DbDataContainer("id", GroundType.LONG, successor.getId()));
 
-    // To add to a set column, must pass in a set containing the value(s) to add. See CasandraClient.addToSet
-    Set<Long> setValues = new HashSet<>();
-    setValues.add(itemId);
-
-    this.dbClient.addToSet("version_successor", "item_id_set", setValues, predicate);
+    this.dbClient.update(newValue, predicate, "version_successor");
     dag.addEdge(parentId, childId, successor.getId());
   }
 

app/dao/versions/cassandra/CassandraVersionSuccessorFactory.java

@@ -20,16 +20,13 @@
 import db.DbClient;
 import db.DbDataContainer;
 import exceptions.GroundException;
+import java.util.ArrayList;
+import java.util.List;
 import models.versions.GroundType;
 import models.versions.Version;
 import models.versions.VersionSuccessor;
 import util.IdGenerator;
 
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-
 public class CassandraVersionSuccessorFactory implements VersionSuccessorFactory {
   private final CassandraClient dbClient;
   private final IdGenerator idGenerator;
@@ -73,11 +70,9 @@ public <T extends Version> List<VersionSuccessor<T>> retrieveFromDatabaseByItemI
     CassandraResults resultSet;
 
     List<VersionSuccessor<T>> versionSuccessors = new ArrayList<>();
-    resultSet = this.dbClient.selectWhereCollectionContains(
-      "version_successor",
-      DbClient.SELECT_STAR,
-      "item_id_set",
-      new DbDataContainer(null, GroundType.LONG, itemId));
+    List<DbDataContainer> predicate = new ArrayList<>();
+    predicate.add(new DbDataContainer("item_id", GroundType.LONG, itemId));
+    resultSet = this.dbClient.equalitySelect("version_successor", DbClient.SELECT_STAR, predicate);
 
     if (resultSet.isEmpty()) {
       throw new GroundException("No VersionSuccessor found with itemId " + itemId + ".");
@@ -142,13 +137,6 @@ public void deleteFromDestination(long toId, long itemId) throws GroundException
     do {
       long dbId = resultSet.getLong("id");
 
-      predicates.clear();
-      predicates.add(new DbDataContainer("id", GroundType.LONG, dbId));
-      Set<Long> value = new HashSet<>();
-      value.add(itemId);
-
-      this.dbClient.deleteFromSet("version_successor", "item_id_set", value, predicates);
-
       predicates.clear();
       predicates.add(new DbDataContainer("id", GroundType.LONG, dbId));
 

scripts/cassandra/cassandra.cql

@@ -22,11 +22,9 @@ CREATE TABLE IF NOT EXISTS version_successor (
     id bigint PRIMARY KEY,
     from_version_id bigint,
     to_version_id bigint,
-    item_id_set set<bigint>
+    item_id bigint
 );
 
-CREATE INDEX IF NOT EXISTS version_successor_ind on version_successor (item_id_set);
-
 CREATE TABLE IF NOT EXISTS item (
     id bigint PRIMARY KEY
 );