add databaseVersion() method for getting the dialect database version

lib/dialects/abstract/query-generator.js

@@ -50,6 +50,10 @@ module.exports = (function() {
       throwMethodUndefined('createTableQuery');
     },
 
+    versionQuery: function(tableName, attributes, options) {
+      throwMethodUndefined('versionQuery');
+    },
+
     describeTableQuery: function(tableName, schema, schemaDelimiter) {
       var table = this.quoteTable(
         this.addSchema({

lib/dialects/abstract/query.js

@@ -83,6 +83,10 @@ module.exports = (function() {
     }
   };
 
+  AbstractQuery.prototype.isVersionQuery = function () {
+    return this.options.type === QueryTypes.VERSION;
+  };
+
   AbstractQuery.prototype.isUpsertQuery = function () {
     return this.options.type === QueryTypes.UPSERT;
   };

lib/dialects/mysql/query-generator.js

@@ -17,6 +17,10 @@ module.exports = (function() {
       return 'SHOW TABLES';
     },
 
+    versionQuery: function() {
+      return 'SELECT VERSION() as `version`';
+    },
+
     createTableQuery: function(tableName, attributes, options) {
       options = Utils._.extend({
         engine: 'InnoDB',

lib/dialects/mysql/query.js

@@ -97,6 +97,8 @@ module.exports = (function() {
       result = data[0];
     } else if (this.isBulkUpdateQuery() || this.isBulkDeleteQuery() || this.isUpsertQuery()) {
       result = data.affectedRows;
+    } else if (this.isVersionQuery()) {
+      result = data[0].version;
     }
 
     return result;

lib/dialects/postgres/query-generator.js

@@ -28,6 +28,10 @@ module.exports = (function() {
       return "SELECT schema_name FROM information_schema.schemata WHERE schema_name <> 'information_schema' AND schema_name != 'public' AND schema_name !~ E'^pg_';";
     },
 
+    versionQuery: function() {
+      return 'SELECT VERSION() as "version"';
+    },
+
     createTableQuery: function(tableName, attributes, options) {
       var self = this;
 

lib/dialects/postgres/query.js

@@ -234,6 +234,8 @@ module.exports = (function() {
         }
 
         return self.callee || (rows && rows[0]) || undefined;
+      } else if (self.isVersionQuery()) {
+        return results[0].version;
       } else {
         return results;
       }

lib/dialects/sqlite/query-generator.js

@@ -28,6 +28,10 @@ module.exports = (function() {
       return "SELECT name FROM `sqlite_master` WHERE type='table' and name!='sqlite_sequence';";
     },
 
+    versionQuery: function() {
+      return "SELECT sqlite_version() as `version`";
+    },
+
     createTableQuery: function(tableName, attributes, options) {
       options = options || {};
 

lib/dialects/sqlite/query.js

@@ -137,6 +137,8 @@ module.exports = (function() {
                     result = metaData.changes;
                   } else if (self.options.type === QueryTypes.UPSERT) {
                     result = undefined;
+                  } else if (self.options.type === QueryTypes.VERSION) {
+                    result = results[0].version;
                   }
 
                   resolve(result);

lib/query-interface.js

@@ -61,6 +61,13 @@ module.exports = (function() {
     });
   };
 
+  QueryInterface.prototype.databaseVersion = function() {
+    return this.sequelize.query(this.QueryGenerator.versionQuery(), null, {
+      raw: true,
+      type: QueryTypes.VERSION
+    });
+  };
+
   QueryInterface.prototype.createTable = function(tableName, attributes, options) {
     var keys = Object.keys(attributes)
       , keyLen = keys.length

lib/query-types.js

@@ -6,4 +6,5 @@ module.exports = {
   BULKUPDATE: 'BULKUPDATE',
   BULKDELETE: 'BULKDELETE',
   UPSERT: 'UPSERT',
+  VERSION: 'VERSION'
 };

lib/sequelize.js

@@ -787,6 +787,10 @@ module.exports = (function() {
     });
   };
 
+  Sequelize.prototype.databaseVersion = function() {
+    return this.queryInterface.databaseVersion();
+  };
+
   Sequelize.prototype.validate = Sequelize.prototype.authenticate;
 
   /**

test/sequelize.test.js

@@ -1118,4 +1118,13 @@ describe(Support.getTestDialectTeaser("Sequelize"), function () {
       })
     }
   })
-})
+
+  describe('databaseVersion', function () {
+    it('should database/dialect version', function () {
+      return this.sequelize.databaseVersion().then(function (version) {
+        expect(typeof version).to.equal('string');
+        expect(version).to.be.ok;
+      });
+    });
+  });
+});
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