feat: fetch unique index information for columns

lib/discovery.js

@@ -157,37 +157,90 @@ function mixinDiscovery(MySQL, mysql) {
   MySQL.prototype.buildQueryColumns = function(schema, table, options = {}) {
     let sql = null;
     if (schema) {
-      sql = paginateSQL('SELECT table_schema AS "owner",' +
-        ' table_name AS "tableName",' +
-        ' column_name AS "columnName",' +
-        ' data_type AS "dataType",' +
-        ' character_maximum_length AS "dataLength",' +
-        ' numeric_precision AS "dataPrecision",' +
-        ' numeric_scale AS "dataScale",' +
-        ' column_type AS "columnType",' +
-        ' is_nullable = \'YES\' AS "nullable",' +
-        ' CASE WHEN extra LIKE \'%auto_increment%\' THEN 1 ELSE 0 END AS "generated"' +
-        ' FROM information_schema.columns' +
-        ' WHERE table_schema=' + mysql.escape(schema) +
-        (table ? ' AND table_name=' + mysql.escape(table) : ''),
-      'table_name, ordinal_position', {});
+      sql = paginateSQL(
+        `SELECT
+            cols.table_schema AS "owner",
+            cols.table_name AS "tableName",
+            cols.column_name AS "columnName",
+            cols.data_type AS "dataType",
+            cols.character_maximum_length AS "dataLength",
+            cols.numeric_precision AS "dataPrecision",
+            cols.numeric_scale AS "dataScale",
+            cols.column_type AS "columnType",
+            cols.is_nullable = 'YES' AS "nullable",
+            CASE WHEN cols.extra LIKE '%auto_increment%' THEN 1 ELSE 0 END AS "generated",
+            indexes.index_name AS "indexName",
+            indexes.non_unique AS "nonUnique",
+            indexes.seq_in_index AS "seqInIndex",
+            indexes.cardinality AS "cardinality",
+            indexes.index_type AS "indexType",
+            CASE WHEN fk.column_name IS NOT NULL THEN 1 ELSE 0 END AS "isForeignKey"
+        FROM
+            information_schema.columns cols
+        LEFT JOIN
+            information_schema.statistics indexes
+        ON
+            cols.table_schema = indexes.table_schema
+            AND cols.table_name = indexes.table_name
+            AND cols.column_name = indexes.column_name
+        LEFT JOIN
+            information_schema.KEY_COLUMN_USAGE fk
+        ON
+            cols.table_schema = fk.table_schema
+            AND cols.table_name = fk.table_name
+            AND cols.column_name = fk.column_name
+            AND fk.referenced_table_name IS NOT NULL
+        WHERE
+            cols.table_schema = ${mysql.escape(schema)}
+        ${table ? ' AND cols.table_name = ' + mysql.escape(table) : ''}
+        `,
+        'cols.table_name, cols.ordinal_position',
+        {},
+      );
     } else {
-      sql = paginateSQL('SELECT table_schema AS "owner",' +
-        ' table_name AS "tableName",' +
-        ' column_name AS "columnName",' +
-        ' data_type AS "dataType",' +
-        ' character_maximum_length AS "dataLength",' +
-        ' numeric_precision AS "dataPrecision",' +
-        ' numeric_scale AS "dataScale",' +
-        ' column_type AS "columnType",' +
-        ' is_nullable = \'YES\' AS "nullable",' +
-        ' CASE WHEN extra LIKE \'%auto_increment%\' THEN 1 ELSE 0 END AS "generated"' +
-        ' FROM information_schema.columns' +
-        (table ? ' WHERE table_name=' + mysql.escape(table) : ''),
-      'table_name, ordinal_position', {});
+      sql = paginateSQL(
+        `SELECT
+            cols.table_schema AS "owner",
+            cols.table_name AS "tableName",
+            cols.column_name AS "columnName",
+            cols.data_type AS "dataType",
+            cols.character_maximum_length AS "dataLength",
+            cols.numeric_precision AS "dataPrecision",
+            cols.numeric_scale AS "dataScale",
+            cols.column_type AS "columnType",
+            cols.is_nullable = 'YES' AS "nullable",
+            CASE WHEN cols.extra LIKE '%auto_increment%' THEN 1 ELSE 0 END AS "generated",
+            indexes.index_name AS "indexName",
+            indexes.seq_in_index AS "indexColumnOrder",
+            indexes.non_unique AS "nonUnique",
+            indexes.cardinality AS "cardinality",
+            indexes.index_type AS "indexType",
+            CASE WHEN fk.column_name IS NOT NULL THEN 1 ELSE 0 END AS "isForeignKey"
+         FROM
+            information_schema.columns AS cols
+         LEFT JOIN
+            information_schema.statistics AS indexes
+         ON
+            cols.table_schema = indexes.table_schema
+            AND cols.table_name = indexes.table_name
+            AND cols.column_name = indexes.column_name
+         LEFT JOIN
+            information_schema.KEY_COLUMN_USAGE AS fk
+         ON
+            cols.table_schema = fk.table_schema
+            AND cols.table_name = fk.table_name
+            AND cols.column_name = fk.column_name
+            AND fk.referenced_table_name IS NOT NULL
+         WHERE
+            cols.table_schema = ${mysql.escape(schema)}
+            ${table ? ' AND cols.table_name = ' + mysql.escape(table) : ''}
+        `,
+        'cols.table_name, cols.ordinal_position',
+        {},
+      );
     }
     if (options.orderBy) {
-      sql += ' ORDER BY ' + options.orderBy;
+      sql += ' ORDER BY ' + 'cols.' + options.orderBy;
     }
     return sql;
   };

test/mysql.discover.test.js

@@ -199,6 +199,23 @@ describe('Discover model primary keys', function() {
   });
 });
 
+describe('Discover user model with index', function() {
+  it('should return user with index', function(done) {
+    db.discoverModelProperties('user', function(err, models) {
+      if (err) {
+        console.error(err);
+        done(err);
+      } else {
+        models.forEach(function(m) {
+          assert(m.tableName.toLowerCase() === 'user');
+          assert(m.properties.email.index);
+        });
+        done(null, models);
+      }
+    });
+  });
+});
+
 describe('Discover model foreign keys', function() {
   it('should return an array of foreign keys for INVENTORY', function(done) {
     db.discoverForeignKeys('INVENTORY', function(err, models) {

test/schema.sql

@@ -208,6 +208,21 @@ LOCK TABLES `RESERVATION` WRITE;
 /*!40000 ALTER TABLE `RESERVATION` ENABLE KEYS */;
 UNLOCK TABLES;
 
+DROP TABLE IF EXISTS `USER`;
+/*!40101 SET @saved_cs_client     = @@character_set_client */;
+/*!40101 SET character_set_client = utf8 */;
+
+CREATE TABLE `USER` (
+  `ID` VARCHAR(20) NOT NULL,
+  `NAME` VARCHAR(100) NOT NULL,
+  `EMAIL` VARCHAR(255) NOT NULL,
+  `PASSWORD` VARCHAR(255) NOT NULL,
+  `CREATED_AT` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  `UPDATED_AT` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  PRIMARY KEY (`ID`),
+  UNIQUE KEY `USER_EMAIL_UNIQUE` (`EMAIL`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;
+
 --
 -- Table structure for table `TESTGEN`
 --