Merge pull request #56 from strongloop/fix/add-drop-indexes

Fix build and drop of primary indexes

Author: Sakib Hasan

lib/ibmdb.js

@@ -851,27 +851,62 @@ IBMDB.prototype.buildIndexes = function(model) {
   var indexClauses = [];
   var definition = this.getModelDefinition(model);
   var indexes = definition.settings.indexes || {};
+  /*!
+    This module did not allow to define indexes the "new" way loopback wants to.
+    - The new way to define indexes in loopback
+    (https://loopback.io/doc/en/lb3/Model-definition-JSON-file.html#indexes)
+      "name_key": {
+        "columns": "name",
+        "unique": true
+      }
+    - The way the module previously accepted indexes:
+      "name_key": {
+        "keys" : {
+          "name": 1
+        }
+      }
+    The module now allows both ways to define the indexes.
+  */
   // Build model level indexes
   for (var index in indexes) {
     var i = indexes[index];
     var statement = new ParameterizedSQL('CREATE');
     if (i.kind) {
       statement.merge(i.kind);
-    } else if (i.unique) {
+    } else if ((i.options && i.options.unique && i.options.unique === true)
+      || i.unique) {
+      // if index unique indicator is configured
       statement.merge('UNIQUE');
     }
-
-    var columns = i.columns.split(',').map(function(val) {
-      return self.escapeName(val);
-    });
+    var indexedColumns = [];
+    var columns = '';
+    // if indexes are configured as "keys"
+    if (i.keys) {
+      // for each field in "keys" object
+      for (var key in i.keys) {
+        // index in asc order
+        if (i.keys[key] !== -1) {
+          indexedColumns.push(key);
+        } else {
+          // index in desc order
+          indexedColumns.push(key + ' DESC');
+        }
+      }
+    }
+    if (indexedColumns.length) {
+      columns = indexedColumns.join(',');
+    } else if (i.columns) {
+      columns = i.columns.split(',').map(function(val) {
+        return self.escapeName(val);
+      });
+    }
 
     statement.merge('INDEX ' + self.escapeName(index) + ' ON ');
     statement.merge(self.schema + '.' + self.tableEscaped(model));
     statement.merge('(' + columns + ')');
 
     indexClauses.push(statement.sql);
   }
-
   return indexClauses;
 };
 

lib/migration.js

@@ -124,13 +124,21 @@ module.exports = function(IBMDB) {
   };
 
   IBMDB.prototype.dropIndexes = function(model, actualIndexes) {
+    var self = this;
     var operations = [];
 
     // If there are indexes for this table then we need to drop them.
     // Generate the statements here to drop all known indexes.
     if (actualIndexes) {
       actualIndexes.forEach(function(i) {
-        var stmt = 'DROP INDEX ' + i.INDNAME;
+        var isPrimaryIndex = i.UNIQUERULE === 'P';
+        var stmt;
+        if (isPrimaryIndex) {
+          stmt = 'ALTER TABLE ' + self.schema + '.' +
+              self.tableEscaped(model) + ' ' + 'DROP PRIMARY KEY';
+        } else {
+          stmt = 'DROP INDEX "' + i.INDNAME + '"';
+        }
         operations.push(stmt);
       });
     }
@@ -145,6 +153,9 @@ module.exports = function(IBMDB) {
     var self = this;
     var sql = [];
     var tasks = [];
+    var pks = this.idNames(model).map(function(i) {
+      return self.columnEscaped(model, i);
+    });
 
     // Create the statements to drop all existing indexes before we start
     // altering the table.
@@ -166,6 +177,13 @@ module.exports = function(IBMDB) {
     // ------------------------------------------------------------------------
     sql = sql.concat(self.buildIndexes(model));
 
+    // add back the primary key index
+    async.forEach(pks, function(pk) {
+      sql.push('ALTER TABLE ' + self.schema + '.' +
+        self.tableEscaped(model) + ' ' + 'ADD PRIMARY KEY (' +
+        pk + ')');
+    });
+
     sql.forEach(function(i) {
       tasks.push(function(cb) {
         self.execute(i, function(err, results) {