/*
* Example with target node:
*
* MATCH (n:ENTITY:table {id: {0}}) -[r:role] - (t {id: {1}})
* RETURN r
*
* Example with relationship indexes:
*
* MATCH (n:ENTITY:table {id: {0}}) -[r:role {index: {1}}] - (t)
* RETURN r
*/
private static String initFindRelationshipQuery(
EntityKeyMetadata ownerEntityKeyMetadata, AssociationKeyMetadata associationKeyMetadata) {
int offset = 0;
StringBuilder queryBuilder = new StringBuilder("MATCH ");
queryBuilder.append("(n:");
queryBuilder.append(ENTITY);
queryBuilder.append(":");
appendLabel(ownerEntityKeyMetadata, queryBuilder);
appendProperties(ownerEntityKeyMetadata, queryBuilder);
queryBuilder.append(") - ");
queryBuilder.append("[r");
queryBuilder.append(":");
appendRelationshipType(queryBuilder, associationKeyMetadata);
offset = ownerEntityKeyMetadata.getColumnNames().length;
if (associationKeyMetadata.getRowKeyIndexColumnNames().length > 0) {
appendProperties(queryBuilder, associationKeyMetadata.getRowKeyIndexColumnNames(), offset);
queryBuilder.append("] - (t");
} else {
queryBuilder.append("] - (t");
appendProperties(
queryBuilder,
associationKeyMetadata
.getAssociatedEntityKeyMetadata()
.getEntityKeyMetadata()
.getColumnNames(),
offset);
}
queryBuilder.append(")");
queryBuilder.append(" RETURN r");
return queryBuilder.toString();
}
@Override
public DuplicateInsertPreventionStrategy getDuplicateInsertPreventionStrategy(
EntityKeyMetadata entityKeyMetadata) {
// Only for non-composite keys (= one column) Neo4j supports unique key constraints; Hence an
// explicit look-up
// is required to detect duplicate insertions when using composite keys
return entityKeyMetadata.getColumnNames().length == 1
? DuplicateInsertPreventionStrategy.NATIVE
: DuplicateInsertPreventionStrategy.LOOK_UP;
}
/*
* Example with association:
*
* MATCH (n:ENTITY:table {id: {0}}) -[r:role] - (e)
* DELETE r
*
* Example with embedded collection:
*
* MATCH (n:ENTITY:table {id: {0}}) -[r:role] - (e:EMBEDDED)
* DELETE r, e
*
* Example with indexes:
*
* MATCH (n:ENTITY:table {id: {0}}) -[r:role {index: {1}}] - (e)
* DELETE r
*/
private static String initRemoveAssociationRowQuery(
EntityKeyMetadata ownerEntityKeyMetadata, AssociationKeyMetadata associationKeyMetadata) {
StringBuilder queryBuilder = new StringBuilder("MATCH ");
queryBuilder.append("(n:");
queryBuilder.append(ENTITY);
queryBuilder.append(":");
appendLabel(ownerEntityKeyMetadata, queryBuilder);
appendProperties(ownerEntityKeyMetadata, queryBuilder);
queryBuilder.append(") - ");
queryBuilder.append("[r");
queryBuilder.append(":");
appendRelationshipType(queryBuilder, associationKeyMetadata);
int offset = ownerEntityKeyMetadata.getColumnNames().length;
boolean hasIndexColumns = associationKeyMetadata.getRowKeyIndexColumnNames().length > 0;
if (hasIndexColumns) {
appendProperties(queryBuilder, associationKeyMetadata.getRowKeyIndexColumnNames(), offset);
}
queryBuilder.append("] - (e");
if (associationKeyMetadata.getAssociationKind() == AssociationKind.EMBEDDED_COLLECTION) {
queryBuilder.append(":");
queryBuilder.append(EMBEDDED);
}
if (!hasIndexColumns) {
appendProperties(
queryBuilder,
associationKeyMetadata
.getAssociatedEntityKeyMetadata()
.getEntityKeyMetadata()
.getColumnNames(),
offset);
}
queryBuilder.append(")");
queryBuilder.append(" DELETE r");
if (associationKeyMetadata.getAssociationKind() == AssociationKind.EMBEDDED_COLLECTION) {
queryBuilder.append(", e");
}
return queryBuilder.toString();
}
