Draft: EHN: file system: link

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patches/patch20220110-6.0-SNAPSHOT/patch.sql

@@ -44,7 +44,8 @@ ALTER TABLE files ADD COLUMN IF NOT EXISTS (
     parent_directory INT UNSIGNED DEFAULT NULL,
     mimetype VARBINARY(255) DEFAULT NULL,
     file_storage_id VARBINARY(255) NOT NULL DEFAULT "DEFAULT",
-    file_key VARBINARY(16000) DEFAULT NULL
+    file_key VARBINARY(16000) DEFAULT NULL,
+    link_target INT UNSIGNED DEFAULT NULL
 );
 
 -- ... and to the corresponding archive_files table.
@@ -54,7 +55,8 @@ ALTER TABLE archive_files ADD COLUMN IF NOT EXISTS (
     parent_directory INT UNSIGNED DEFAULT NULL,
     mimetype VARBINARY(255) DEFAULT NULL,
     file_storage_id VARBINARY(255) NOT NULL DEFAULT "DEFAULT",
-    file_key VARBINARY(16000) DEFAULT NULL
+    file_key VARBINARY(16000) DEFAULT NULL,
+    link_target INT UNSIGNED DEFAULT NULL
 );
 
 -- no two files at the same path are allowed.
@@ -64,12 +66,16 @@ ALTER TABLE files ADD FOREIGN KEY (parent_directory) REFERENCES entities (id);
 ALTER TABLE archive_files ADD FOREIGN KEY (parent_directory) REFERENCES entities (id) ON DELETE CASCADE;
 
 
-ALTER TABLE entities MODIFY COLUMN `role` enum('RECORDTYPE','RECORD','FILE','DOMAIN','PROPERTY','DATATYPE','ROLE','QUERYTEMPLATE', 'DIRECTORY') COLLATE utf8_unicode_ci NOT NULL;
+ALTER TABLE entities MODIFY COLUMN `role` enum('RECORDTYPE','RECORD','FILE','DOMAIN','PROPERTY','DATATYPE','ROLE','QUERYTEMPLATE', 'DIRECTORY', 'LINK') COLLATE utf8_unicode_ci NOT NULL;
 
 -- Add a new special role "DIRECTORY"
 INSERT IGNORE INTO entities (id, description, role, acl) VALUES (9, "The directory role.", "ROLE", 0);
 INSERT IGNORE INTO name_data (domain_id, entity_id, property_id, value, status, pidx) VALUES (0, 9, 20, "DIRECTORY", "FIX", 0);
 
+-- Add a new special role "LINK"
+INSERT IGNORE INTO entities (id, description, role, acl) VALUES (10, "The link role.", "ROLE", 0);
+INSERT IGNORE INTO name_data (domain_id, entity_id, property_id, value, status, pidx) VALUES (0, 10, 20, "LINK", "FIX", 0);
+
 -- In the default file storage back-end the key is just the path.
 UPDATE files SET file_key=path;
 UPDATE archive_files SET file_key=path;