While starting a new application, we often wonder which database to use, especially if the application is database intensive. Recently I came across Realm, which is really well-built and surprisingly very fast compared to SQLite. In this post, I aim at showing how Realm compares to SQLite.
Let’s start with looking at basic CRUD operations in Realm.
Create:
Read:
Update:
Delete:
Now let’s look at the comparison between Realm and SQLite.
1. Architecture
Realm does not use SQLite as its engine, rather it is a database built from scratch to run directly on phones, tablets and wearables. Realm is an object oriented database that uses C++ as its core. However, SQLite uses a transactional SQL database engine.
2. Easy to Use
Realm is easy to use as it uses objects for storing data. Realm data models are defined using normal Java classes that are a subclass of RealmObject. This class can define properties of primary keys, required fields etc. using simple annotations. Also, there is no requirement for converting the Realm query results into objects for further use, this conversion is handled automatically by Realm. Realm query results are returned in a generic RealmResults instance which is a collection of the model class. This RealmResults instance is iterable like a List. However, the SQLite query results are returned in a Cursor object.
3. Cross Platform
Realm stores its data in a native object format where the objects are stored in a universal table-based format using C++ as its core, rather than storing them as is in their language specific format. This makes Realm easy to use across multiple languages, platforms and queries.
4. Speed
Realm performance is faster than SQLite, almost 10x faster according to the benchmark results. An example of this is- data fetched by Realm queries have a better performance enhancement than the insert queries as compared to SQLite.
5. Data Synchronization
The data in Realm is never copied, it works on live objects. Using Realm queries, we get a list of object references thereby working on the original Realm data. Thus, any changes made to the queried data is reflected in the actual stored data as well after a simple commit. However, in SQLite, we get a copy of the data from the database through a query. Thus, using SQLite, any changes made on the queried data need to be persisted by writing them back to the database again.
Companies using Realm:
A few companies using Realm are Amazon, Google, Starbucks, Intel, Ebay, Adidas, Zynga, Nike, IBM, and CISCO.
Limitations:
Realm currently has a few limitations:
Realm does not have support for auto-incrementing ID’s and composite keys.
In order to maintain a balance between flexibility and performance, Realm imposes a certain limitations on various aspects of storing information in a Realm which include:
The upper limit on the name of a class is 57 characters, which includes the _class prefix.
The field names have an upper limit of 63 characters.
There is no support for nested transactions.
String and byte arrays cannot be greater than 16 MB.
There is no support for final, transient, and volatile variables.
Realm model classes can only extend the Realm object.
Realm model class must include the default empty constructor.
There is currently support for only ‘Latin Basic’, ‘Latin Supplement’, ‘Latin Extended A’, and ‘Latin Extended B’ (UTF-8 range 0-591) in sorting and case-insensitive string matches. Further, setting the case insensitive flag in queries when using equalTo(), contains(), endsWith() or beginsWith() will only work on characters from the English locale.
Although Realm files can be handled concurrently by multiple threads, we cannot hand over Realms, Realm objects, queries, and results between threads.
Realm files cannot be accessed by concurrent processes, they can only be accessed by one process at a time. Different processes should either copy Realm files or create their own.
RealmObject are live objects, and might be updated by changes from other threads. Although two Realm objects returning true for RealmObject.equals() must have the same value for RealmObject.hashCode(), the value is not stable, and should neither be used as a key in HashMap nor saved in HashSet.
SQL is the most renowned Fourth Generation Programming Language (4GL). 4GL means that programmers only define what the result looks like as opposed to how the outcome ought to be calculated by the database. SQL is not a full-fledged programming language in which you can write applications and is a pillar of web development (back-end). Generally, this decisive programming paradigm has been a key component for ad-hoc queries run for data introspection carried out by human users directly with SQL rather than with a user interface.
SQL programming can be productively used to search, insert, delete or update database records. However, its functionalities do not end here. Actually, it can do plenty of things including, yet not constrained to, upkeep and streamline of databases. RDBMS like Oracle, MySQL Database, Sybase, MS SQL Server, and so on use SQL.
Beneath we’ve gathered a rundown of the most significant abilities for a SQL Developer. We positioned the top abilities dependent on the level of SQL Developer resume they showed upon. For instance, 15% of SQL Developer resumes contained Database as an aptitude. We should discover what abilities a SQL Developer entirely so as to be fruitful in the work environment.
What skills are required to be a SQL Developer?
If you’re planning to become a Structured Query Language Developer, (sometimes pronounced as “sequel”), now is the right time to make the move. These specialists are in high demand as corporations push to implement their digital revolution strategies and become data-driven organizations. This role requires you to plan, construct and maintain databases. You are responsible for all aspects of it which also includes:
Database
The database is an orderly assortment of data. Databases bolster stockpiling and control of information. Databases make information handling simple. For example, an online phone catalogue would utilize a database to store information relating to individuals, telephone numbers, other contact subtleties, and so on. Each company, service provider and organization around you utilize a database to manage billing, customer related issues, to deal with error information, and so forth. We should likewise consider Facebook. It needs to store, control and present information identified with individuals, their companions, part exercises, messages, promotions and parcel more. Likewise, there is an unending number of examples for the same.
It is utilized to screen the general execution of the database to prescribe and start activities to improve/enhance performance and make Snapshot Replication for the development and testing Databases across various Servers. It is used to make records and perspectives, put away techniques to upgrade database/application execution.
SQL
Well, knowing SQL is the most fundamental and foremost requirement when you start on the path of becoming a SQL developer. SQL represents Structured Query Language and it allows you to control and access databases. SQL by expansion is truly adept at working with a lot of information. SQL is even useful for troublesome information control. It is used to test Performance Accuracy related inquiries under SQL Server and improve the exhibition of questions with adjustment in T-SQL questions, standardized tables, set up joins and create indexes wherever necessary. It facilitates the creation of complex queries using table joins (inner and outer), temporary tables and table variables.
SSIS
SQL Server Integration Service (SSIS) is a part of the Microsoft SQL Server database programming that can be utilized to execute a wide scope of information relocation assignments. SSIS is a quick and adaptable information warehousing instrument utilized for information extraction, stacking and change like cleaning, aggregating, merging data, and so forth. It makes it simple to move information starting with one database then onto the next database. SSIS can separate information from a wide assortment of sources like SQL Server databases, Excel records, Oracle and DB2 databases, and so on. SSIS likewise incorporates graphical instruments and wizards for performing work process capacities like sending email messages, FTP activities, data sources, and destinations.
T-SQL
T-SQL (Transact-SQL) is a lot of programming expansions from Sybase and Microsoft that add a few highlights to the Structured Query Language (SQL), including transaction control, exception and error handling, row processing and declared variables. All applications that interact with SQL Server do as such by sending T-SQL proclamations to the server. T-SQL questions incorporate the SELECT articulation, labelling output columns, restricting rows and modifying a search condition. T-SQL identifiers, in the interim, are utilized in all databases, servers, and database protests in SQL Server. These incorporate the accompanying tables, imperatives, put away methodology, perspectives, segments and information types. T-SQL identifiers should each have a one of a kind name, is allocated when an article is made and are utilized to distinguish an item.
Other Programming Languages
If you haven’t worked with SQL previously, you’ll see it’s a moderately clear revelatory language where you compose queries that either adjusts the database or recover records. Ideally, proficient SQL engineers ought to have experience working in a development environment like Oracle SQL Developer. Other programming necessities differ across associations. For instance, you may be developing applications written in Java, C++ and C#, so information on these will assist you with working together with different groups. When working with MySQL, you in all likelihood need to have involvement in PHP. Similarly, recognition with the .NET system is helpful, particularly on the off chance that you’ll be having some expertise in Microsoft SQL Server. A foundation in Unix is another enormous addition to it. You ought to be efficient in CLI, so getting Bash or Windows batch scripts is another approach to enable your resume to stick out.
It’s a job that gets even more complicated as databases convert into data lakes, and you need to keep your skills updated. But with the right experience and certifications, you can assure a knock from the employers on your door.
Here’s an overview of the skills and educational background needed to dive into the SQL Developer role:
PL/SQL: A thorough knowledge of structured query language or correlated programming language to work effortlessly on database design.
SQL Server Reporting Services (SSRS): This service aids in report generation for several databases so that you can be sure of all database objects and units encompassed in the database.
SQL Server Integration Services (SSIS): This service helps you with the integration of multiple databases, database objects and entities as per your requirement.
Microsoft SQL Server: This is the most difficult yet intriguing job for SQL developer where he has to work on server performance, integrity as well as server maintenance. This is one of the highly paid SQL Developer skills where developers get attractive remuneration and other opportunities too.
Analytical skills: Developers must analyze and understand the needs of the user and then design the software accordingly to meet those needs.
Creativity: Developers must be creative enough to find new solutions to conventional problems.
Detail-oriented: Developers usually work on several parts of an application or system simultaneously and therefore must be able to focus and pay attention to even the minute details.
Interpersonal skills: Developers must be able to work in harmony with others who help in developing and creating successful software.
Problem-solving skills: Since developers are in charge of software from beginning to end, they should be capable of solving problems that may occur along the design process.
Communication skills: Developers must be capable of giving able to give clear instructions to their teammates. They should also be able to explain to their customers how the software works and answer any queries that arise.
Systematic skills, smart organization skills, fine detailing, maximum accuracy, great knowledge of structured programming language, decent experience in RDBMS and knowledge of maintaining relationships between different data objects. You need to be a quick performer and you must know how to work under stress and constant pressure. The future of SQL is really bright and most of the successful SQL professionals ensure that they know each and everything about current trends of the database and stay updated about the technical market.
What are the responsibilities of an SQL Developer?
Application of DML and DCL statements
Build appropriate and valuable report deliverables
Create procedures and scripts
Develop top-notch database solutions
Develop, execute and modify stored procedures
Examine SQL queries
Guarantee performance, safety, and readiness of databases
Handle troubleshooting database problems
Provide reports
Research necessary data
Why should you choose SQL as your career?
SQL is a massive technology. The future scope of being an SQL Developer it is not just limited to Computer Science, but you can see it revolving around Retail, Finance, Healthcare, Science & Technology, Public Sector, in short everywhere. All organizations need a database for the storage of their data. There are endless reasons why you could SQL career. A few are listed below:
Combine data from multiple resources: Integrating data from several resources may be consuming a lot of time, but with SQL, you may simply combine the specific fields or merge the complete database.
Everlasting: The image below shows a report of StackOverflow’s survey conducted in 2017 where SQL stands second in terms of popularity ensuring that SQL is here to stay for times to come.
Free: SQL is open-source which means that SQL is completely free to use and distribute. As far as learning is concerned, you just have to bear the initial training charges of SQL certification, later on, you need not pay for any tool or software to practice SQL. SQL is executed using XAMP/WAMP server, which is an open-source tool for executing the queries.
High in Demand: If you search the internet for jobs for SQL Developers, there are more than 25k results. According to an analysis, SQL has been mentioned in 35.7% of advertisements, which is 1.39 times higher than the advertisements of Python and other Data Analytical languages.
Integration: You can utilize SQL queries with the incorporation of other programming languages like PHP or Java depending as per your requirement.
Manage bulk of data: When you have a large collection of data, then it becomes really difficult for the conventional database software to manage them. In this case, SQL acts as a blessing. Whether there are a thousand records or a million, SQL is fully equipped to manage a huge amount of data of all types.
Simple: SQL is the simplest programming language as compared to its contemporaries. One can easily learn the basics and fundamentals of SQL within a week or two.
Standard: SQL development has been around for 30 years now and without any doubt, it is going to stay for a good 30 years or more too staying true to the old proverb, “Old is Gold”.
The base of data visualization tools: All data visualization tools utilize SQL for their functioning. Therefore learning SQL will help you get a better understanding of all such tools.
CONCLUSION
SQL Developers are sought after because of the expanding dependence on the information. Turning into a SQL engineer can be a fulfilling and satisfying vocation. The path towards it is generally simply contrasted with other specialized vocations. Microsoft SQL Server is among the best 3 RDBMS frameworks and getting the right skills for turning into a SQL Server developer will work well for you and open many job opportunities.
Most SQL developers are either database specialists or veterans in managing database advancement. There are various kinds of SQL relying upon the stage you use, however, they all play out similar essential capacities—recover, include, alter, and erase database information.
