Addressing review comments.

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/TermValueSetConcept.java

@@ -35,8 +35,12 @@ import java.util.List;
 import static org.apache.commons.lang3.StringUtils.left;
 import static org.apache.commons.lang3.StringUtils.length;
 
-@Table(name = "TRM_VALUESET_CONCEPT", indexes = {
+/*
-	@Index(name = "IDX_VALUESET_CONCEPT_CS_CD", columnList = "SYSTEM_URL, CODEVAL")
+ * DM 2019-08-01 - Do not use IDX_VALUESET_CONCEPT_CS_CD; this was previously used as an index so reusing the name will
+ * bork up migration tasks.
+ */
+@Table(name = "TRM_VALUESET_CONCEPT", uniqueConstraints = {
+	@UniqueConstraint(name = "IDX_VS_CONCEPT_CS_CD", columnNames = {"VALUESET_PID", "SYSTEM_URL", "CODEVAL"})
 })
 @Entity()
 public class TermValueSetConcept implements Serializable {

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/TermValueSetExpansionStatusEnum.java

@@ -20,10 +20,23 @@ package ca.uhn.fhir.jpa.entity;
  * #L%
  */
 
+/**
+ * This enum is used to indicate the expansion status of a given ValueSet in the terminology tables. In this context,
+ * an expanded ValueSet has its included concepts stored in the terminology tables as well.
+ */
 public enum TermValueSetExpansionStatusEnum {
 
+	/**
+	 * This status indicates the ValueSet is waiting to be picked up and expanded by a scheduled task.
+	 */
 	NOT_EXPANDED,
+	/**
+	 * This status indicates the ValueSet has been picked up by a scheduled task and is mid-expansion.
+	 */
 	EXPANSION_IN_PROGRESS,
+	/**
+	 * This status indicates the ValueSet has been picked up by a scheduled task and expansion is complete.
+	 */
 	EXPANDED
 	
 }

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/term/BaseHapiTerminologySvcImpl.java

@@ -1496,7 +1496,6 @@ public abstract class BaseHapiTerminologySvcImpl implements IHapiTerminologySvc,
 	}
 
 	@Scheduled(fixedDelay = 600000) // 10 minutes.
-	@Transactional
 	@Override
 	public synchronized void preExpandValueSetToTerminologyTables() {
 		new TransactionTemplate(myTxManager).execute(new TransactionCallbackWithoutResult() {

hapi-fhir-jpaserver-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/tasks/HapiFhirJpaMigrationTasks.java

@@ -133,15 +133,18 @@ public class HapiFhirJpaMigrationTasks extends BaseMigrationTasks<VersionEnum> {
 			.references("TRM_VALUESET", "PID");
 		termValueSetConceptTable.addColumn("SYSTEM_URL").nonNullable().type(BaseTableColumnTypeTask.ColumnTypeEnum.STRING, TermCodeSystem.MAX_URL_LENGTH);
 		termValueSetConceptTable.addColumn("CODEVAL").nonNullable().type(BaseTableColumnTypeTask.ColumnTypeEnum.STRING, TermConcept.MAX_CODE_LENGTH);
-		termValueSetConceptTable
-			.addIndex("IDX_VALUESET_CONCEPT_CS_CD")
-			.unique(false)
-			.withColumns("SYSTEM_URL", "CODEVAL");
 		termValueSetConceptTable.addColumn("DISPLAY").nullable().type(BaseTableColumnTypeTask.ColumnTypeEnum.STRING, TermConcept.MAX_DESC_LENGTH);
 		version.onTable("TRM_VALUESET_CONCEPT")
 			.renameColumn("CODE", "CODEVAL", true, true)
 			.renameColumn("SYSTEM", "SYSTEM_URL", true, true);
 
+		version.startSectionWithMessage("Processing table: TRM_VALUESET_CONCEPT, swapping index for unique constraint");
+		termValueSetConceptTable.dropIndex("IDX_VALUESET_CONCEPT_CS_CD");
+		termValueSetConceptTable
+			.addIndex("IDX_VS_CONCEPT_CS_CD")
+			.unique(true)
+			.withColumns("VALUESET_PID", "SYSTEM_URL", "CODEVAL");
+
 		// TermValueSetConceptDesignation
 		version.startSectionWithMessage("Processing table: TRM_VALUESET_C_DESIGNATION");
 		version.addIdGenerator("SEQ_VALUESET_C_DSGNTN_PID");