Added new method getLastInsertID()

Author: denissimon

Sources/SQLiteAdapter/SQLiteAdapter.swift

@@ -64,6 +64,7 @@ public protocol SQLiteType {
     func getRow(sql: String, valuesToBind: SQLValues?, valuesToGet: SQLValues) throws -> [SQLValues]
     func getAllRows(in tableName: String, valuesToGet: SQLValues) throws -> [SQLValues]
     func getByID(in tableName: String, id: Int, valuesToGet: SQLValues) throws -> SQLValues
+    func getLastInsertID() throws -> Int
     func vacuum() throws
     func resetAutoincrement(in tableName: String) throws
     func query(sql: String, valuesToBind: SQLValues?) throws
@@ -417,6 +418,22 @@ open class SQLite: SQLiteType {
         }
     }
 
+    public func getLastInsertID() throws -> Int {
+        let sqlStatement = try prepareStatement(sql: "SELECT last_insert_rowid();")
+        defer {
+            sqlite3_finalize(sqlStatement)
+        }
+        
+        try bindPlaceholders(sqlStatement: sqlStatement, valuesToBind: nil)
+        
+        guard sqlite3_step(sqlStatement) == SQLITE_ROW else {
+            throw SQLiteError.Step(getErrorMessage(dbPointer: dbPointer))
+        }
+        let id = sqlite3_column_int(sqlStatement, 0)
+        log("successfully got last_insert_id: \(id)")
+        return Int(id)
+    }
+    
     /// Repack the DB to take advantage of deleted data
     public func vacuum() throws {
         let sql = "VACUUM;"