#3354 Use 4000 for DB Lob detection with distinct query

- Use 4000 to match the DB2 logic for considering a column a lob (for distinct etc)
- Rename distinctNoLobs -> platformDistinctNoLobs
- Rename  isDbLob() -> isLobForPlatform()
- Rename unselectLobs() -> unselectLobsForPlatform()

ebean-core/src/main/java/io/ebeaninternal/server/deploy/BeanProperty.java

@@ -1182,14 +1182,14 @@ public class BeanProperty implements ElPropertyValue, Property, STreeProperty {
    * Returns true if this <code>isLob()</code> or the type will effectively map to a lob.
    */
   @Override
-  public boolean isDbLob() {
+  public boolean isLobForPlatform() {
     if (lob) {
       return true;
     }
     switch (dbType) {
       case DbPlatformType.JSON:
       case DbPlatformType.JSONB:
-        return dbLength == 0 || dbLength > 255; // must be analog to DbPlatformTypeMapping.lookup
+        return dbLength == 0 || dbLength > 4000; // must be analog to DbPlatformTypeMapping.lookup
       case DbPlatformType.JSONBlob:
       case DbPlatformType.JSONClob:
         return true;

ebean-core/src/main/java/io/ebeaninternal/server/deploy/DynamicPropertyAggregationFormula.java

@@ -63,7 +63,7 @@ class DynamicPropertyAggregationFormula extends DynamicPropertyBase {
   }
 
   @Override
-  public boolean isDbLob() {
+  public boolean isLobForPlatform() {
     return false;
   }
 

ebean-core/src/main/java/io/ebeaninternal/server/query/STreeProperty.java

@@ -33,7 +33,7 @@ public interface STreeProperty extends ScalarDataReader<Object> {
   /**
    * Returns true, if this is a lob property from db-perspective.
    */
-  boolean isDbLob();
+  boolean isLobForPlatform();
 
   /**
    * Return true if the property is an embedded type.

ebean-core/src/main/java/io/ebeaninternal/server/query/SqlTreeBuilder.java

@@ -48,7 +48,7 @@ public final class SqlTreeBuilder {
   private final SpiQuery.TemporalMode temporalMode;
   private SqlTreeNode rootNode;
   private boolean sqlDistinct;
-  private final boolean distinctNoLobs;
+  private final boolean platformDistinctNoLobs;
   private final SqlTreeCommon common;
 
   /**
@@ -63,7 +63,7 @@ public final class SqlTreeBuilder {
     this.query = null;
     this.subQuery = false;
     this.distinctOnPlatform = false;
-    this.distinctNoLobs = false;
+    this.platformDistinctNoLobs = false;
     this.queryDetail = queryDetail;
     this.predicates = predicates;
     this.temporalMode = SpiQuery.TemporalMode.CURRENT;
@@ -98,7 +98,7 @@ public final class SqlTreeBuilder {
     this.predicates = predicates;
     this.alias = new SqlTreeAlias(request.baseTableAlias(), temporalMode);
     this.distinctOnPlatform = builder.isPlatformDistinctOn();
-    this.distinctNoLobs = builder.isPlatformDistinctNoLobs();
+    this.platformDistinctNoLobs = builder.isPlatformDistinctNoLobs();
     String fromForUpdate = builder.fromForUpdate(query);
     CQueryHistorySupport historySupport = builder.historySupport(query);
     CQueryDraftSupport draftSupport = builder.draftSupport(query);
@@ -269,8 +269,8 @@ public final class SqlTreeBuilder {
     if (joinList != null) {
       joinList.add(selectNode);
     }
-    if (sqlDistinct && distinctNoLobs) {
-      selectNode.unselectLobs();
+    if (sqlDistinct && platformDistinctNoLobs) {
+      selectNode.unselectLobsForPlatform();
     }
     return selectNode;
   }

ebean-core/src/main/java/io/ebeaninternal/server/query/SqlTreeNode.java

@@ -82,6 +82,6 @@ interface SqlTreeNode {
   /**
    * Unselect lobs (for distinct queries on DB2 and Oracle).
    */
-  default void unselectLobs() {
+  default void unselectLobsForPlatform() {
   }
 }

ebean-core/src/main/java/io/ebeaninternal/server/query/SqlTreeNodeBean.java

@@ -379,16 +379,16 @@ class SqlTreeNodeBean implements SqlTreeNode {
 
 
   @Override
-  public void unselectLobs() {
+  public void unselectLobsForPlatform() {
     if (children != null) {
       for (SqlTreeNode child : children) {
-        child.unselectLobs();
+        child.unselectLobsForPlatform();
       }
     }
     if (hasLob()) {
       List<STreeProperty> lst = new ArrayList<>();
       for (STreeProperty prop : properties) {
-        if (!prop.isDbLob()) {
+        if (!prop.isLobForPlatform()) {
           lst.add(prop);
         }
       }
@@ -399,7 +399,7 @@ class SqlTreeNodeBean implements SqlTreeNode {
 
   private boolean hasLob() {
     for (STreeProperty prop : properties) {
-      if (prop.isDbLob()) {
+      if (prop.isLobForPlatform()) {
         return true;
       }
     }