About Us

The ever changing database management challenges
With the rapid changes of modern databases, database administrators and developers have to learn and manage new features provided by databases with short period of time. There is always a time gap between fully mastering new features and actually implementing the new features in production.

Easy-to-use AI enabled tools for SQL & database performance tuning
Tosska Technologies is a company that focuses in providing solutions for database and SQL related performance optimization and improvements. Our mission is to help users to smooth out the hurdle by our new technologies. Indeed Tosska is one of the very few companies in the world that focus in using artificial intelligence technology to solve various database performance problems. It is our goal to help our customers to reduce their hardware investment; increase their database applications service level and free up their human resources for more strategic activities with our innovative technologies.

Our Products

The Tosska SQL Tuning Expert Products Family

Not just another SQL Tuning tool !
Most SQL tuning products in the market aim to provide better query plan visualization, better statistics analysis, high cost query plan steps indication or even rule-of-thumb syntax recommendations. But very few of them can provide satisfactory tuning results directly. They require users to have in-depth SQL tuning knowledge to manually intervene the SQL tuning process amid their busy daily duties. In fact users are looking for one-button-solution tool that have all the required SQL tuning knowledge built-in and can tune a SQL statement automatically without the need of users’ intervention. If you are looking for such tools, these are the products you must look into !

World’s Leading A.I. SQL Rewrite technology for SQL
Manually rewriting SQL syntax to tune a SQL statement is commonly adopted by experienced developers and DBAs, but the effort and cost to rewrite a SQL statement is quite expensive. Tosska A.I. SQL Rewrite Engine not only saves the developer’s time to rewrite a problematic SQL statement to make it faster, but it also explores the potential best SQL syntax that even an experienced developer cannot discover. Tosska A.I. rewritten SQL syntax can work with our Hints-injection algorithm to further explore more potential query plans that even most experienced developers cannot achieve.


Tosska SQL Tuning Expert (TSES™) for SQL Server®

There are not many SQL tuning tools for SQL Server database that can provide automated direct SQL tuning results. Tosska SQL Tuning Expert (TSES™) for SQL Server® is a a one-button-solution tool that can tune SQL Server SQL statements automatically without the need of your intervention. You can just sit back, relax, and wait for the best SQL alternative to come up on your screen.

Probably the World’s First SQL Server A.I. SQL Tuning Tool for SET ROWCOUNT N
Many people do not know that the Set Rowcount N setting can affect the SQL’s query plan and some SQLs’ performance may be degraded and resulted in an even worse query plan. Tosska SQL Tuning Expert for SQL Server is probably the first tool that can solve this problem automatically with our A.I. engine.

Powerful Cold Cache SQL Tuning for Infrequent Executed SQL Statements
Cold cache will significantly affect the performance of a SQL statement. A good performance SQL for hot cache may not be performing well in a cold cache environment. Tosska SQL Tuning Expert for SQL Server provides a handy function for users to benchmark SQL alternatives in both environments without complicated manual operations.

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Tosska SQL Tuning Expert (TSEM™) for MySQL®
As a member of the TSE product family, TSEM™ provides all the automatic A.I. machine tuning capability of TSE but tailors for the MySQL database. It is a one-button-solution tool that can tune MySQL SQL statement automatically without the need of your intervention. You no longer need to rewrite or try every possible Hints combination manually for a problematic SQL statement to explore potential better performance execution plans, since all those hard tasks are released by our embedded AI engine.

Probably the World’s ONLY A.I.-based SQL Rewrite solution for MySQL database
It not only saves developer’s time to rewrite a problematic SQL statement to make it faster, but also explores the potential best SQL syntax that even an experienced developer cannot discover. Tosska A.I. rewritten SQL syntax can also work with our Hints-injection algorithm to further explore more potential query plans that even most experienced developers cannot achieve.
A 100 times faster SQL rewrite is generated on the right hand side.

Tosska proprietary Tree Plan format for your easy understanding
Tosska SQL Tuning Expert (TSEM™) for MySQL® has a market leading explain plan function for MySQL. The proprietary Tree Plan format provides rich statistics information like what is provided by Tubular Explain from MySQL, as well as a hierarchical structure like what is displaying in visual plan. The beauty is that all such information can be displayed in a small window for easy reading.

Tosska Tree Plan

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Tosska SQL Tuning Expert for Oracle® (TSE™ and TSE Pro™) version 4

 

 
Targeted for the Oracle database, Tosska SQL Tuning Expert (TSE™) for Oracle® and Tosska SQL Tuning Expert Pro (TSE Pro™) for Oracle® are complete SQL tuning solutions that provide SQL syntax rewrite, Query Hints injection and index recommendation to maximize the performance of a SQL without compromise in any specific feature’s limitation.

They give users the ultimate SQL performance solution by just point and click without the need of user’s involvement. What you have to do is to input your problematic SQL statement into the product and press a button. You don’t have to do analysis, guessing or testing during the entire SQL tuning process. The improved SQL statement will be benchmarked with your original SQL statement side by side without suspicion.

World’s Leading A.I. SQL Rewrite technology for Oracle database
Tosska’s A.I. SQL Rewrite plus the A.I. Hints Injection Engine is the world’s leading machine SQL Tuning technology for Oracle database. It saves developer’s time to rewrite a problematic SQL by exploring the potenial best SQL syntax and hints injection that even an experienced developer cannot discover.

Plan Control feature to tune your SQL even if you don’t have the source code
Tosska SQL Tuning Expert Pro (TSE Pro™) also comes with an innovative Plan Control function that improves your SQL performance without touching your program source code. Users can even deploy different performance query plans for various sizes of production databases without the effort of keeping multiple versions of the program source, it is especially suitable for package application users who don’t own the source code of their applications. For application developers, a problematic SQL statement can be improved without going through the time-consuming unit test, integration test and program implementation required in software development cycle.

Intelligent Workload-Based Index Advisor
Apart from the intelligent SQL tuning features, a powerful indexes recommendation function is also provided in TSE Pro™ to help users to review and explore more potential indexes that are helpful but may be missing in current database schema.

It is an intelligent and cost-aware index advice engine that helps users to review their existing database schema if there are any new indexes which can help to improve a given SQL workload. The engine can handle up to thousands of SQL statements and give you a reasonable recommendation that even human experts cannot achieve.

Product feature comparison of TSE Pro™ and TSE™

View Details | Free Download – TSE™ / TSE Pro™ | Buy License – TSE™ / TSE Pro™

 

Tosska In-Memory Maestro (TIM™) for Oracle® automates the In-memory SQL optimization process and provide In-memory objects recommendations for a given SQL workload with our proprietary artificial intelligent engine.

Tosska In-memory Maestro (TIM™) also provides user friendly In-memory simulation function for user to virtually evaluate their in-memory table objects for one SQL or a given SQL workload captured from SGA or AWR without actually populating those table objects.





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Our Company

Tosska Technologies Limited is a young and energetic company that provides intelligent database tuning tools to help our customers to optimize their databases performance to the maximum within the current database and hardware limitation.

With the rapid changes of modern databases, database administrators and developers have to learn and manage new features provided by databases with short period of time, there is always a time gap between fully mastering new features and actually implementing the new features in production.

Our mission is to help users to smooth out the hurdle by our new technologies. Furthermore, Tosska is one of the very few companies in the world that focuses on using artificial intelligence technology to solve various database performance problems. It is our goal to help our customers to reduce their hardware investment; increase their database applications service level and free up their human resources for more strategic activities with our innovative technologies.

Tosska has a very strong technical team. Our CTO has over twenty year experiences in the Artificial Intelligent software development field supported by a development team with solid database management related software development experience in fortune 500 international corporations.

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Click to view Tosska SQL Tuning Expert Pro (TSES Pro™) for SQL Server 2.0.0 Release Notes

Create index oracle

Indexes are among the most useful and underutilized components of SQL. The user can create an Oracle index and store values along with their location in it.

Similar to the index at the end of a book, an index enables the user to go straight to the data they are interested in. Indexes are most useful when a user has to find a few rows. Therefore, they can use an index in statements that return a handful of rows – after creating one, of course!

Simple Techniques to Create an Index in Oracle Database

Creating an index is a simple task in MySQL query optimization as you only need to know two things:

  • The columns that require indexing
  • The name you will give the index

Here’s how to create one:

create index <indexname> on <tablename> ( <col1>, <col2>, <col3>, … <coln> );

Eg. create index cars_colour_metallic on cars (colour);

However, there are a few things to know about indexes before you begin:

  • You can place several columns in a single index, which then becomes a composite or compound index.

For instance, in the above example, you could also add the types of cars in the index like this: create index cars_colour_metallic on cars (colour, type);

  • The order in which you set columns in the index affects its use by the optimizer.

Next, let’s take a look at two of the most important index types users create in Oracle.

Two Major Index Types – and When to Pick Each

There are several kinds of indexes in the Oracle database that can improve your SQL. However, one of the most significant decisions you’ll have to make is likely to involve choosing between B-trees and bitmaps.

Create Index Oracle: B-tree Versus Bitmap Indexes

B-trees:– Indexes are in balanced B-tree format by default, which means all the leaf nodes are located at the same depth. It takes equal effort (O(log n)) to access any value, and one leaf index entry contains one row of data.

Bitmap:- Bitmaps also store indexed values, but in a completely different manner as compared to B-trees. In it, one value entry is associated with a range of row values. A bitmap has a series of 1s (yes) and 0s (no) to indicate whether any of the range rows contains the value or not.

One major difference between these two index types is that a B-tree doesn’t include null indexed values; a bitmap does. A bitmap can, therefore, answer some statements during MySQL query optimization, such as targeted index searches in which the column has a null value.

Although this won’t work for a B-tree, the user can add a constant at the end of an index to turn it into a composite index.

Bitmaps are also helpful because compressing the bits is simpler, which is why a bitmap index is generally smaller as compared to a B-tree index with identical data.

Why You Need to Keep a Check on the Indexes You Create

With all the benefits an index provides, it is important to create as few of them as possible. This is because you may end up creating one for every specific requirement and forget about them over time. The same goes for other users who may come and go on your team. And no one will have a clue why Brad needed to create that six-column function-based nightmare.

Since you don’t know if the index in question is only used for year-end reporting or never used, you cannot drop an index whenever you want. This can result in awkward situations where a table contains more indexes than columns!

So, if you’re unsure between two excellent indexes and one “good enough” index, it is better to choose the latter. And don’t forget to test!

MySQL database and SQL

A database is the cornerstone of any application. For this reason, maintaining one or more backup and recovery options remains a priority for every database professional. There are multiple alternatives you can choose from as per the specific needs of your organization’s database.

In this post, we will examine some of the most popular back-ups and restore strategies for MySQL database and SQL. We will also touch upon the reasons why databases require backups on a regular basis.

Why Do We Need Backups for MySQL Database?

As a DBA, you’ll need backup and recovery to support data in multiple cases, such as:

Discrepancies in Data: Users may accidentally delete or update incorrect data in the primary or replica node.

Data Centre Failure: An indefinite power outage or internet connectivity issue can spell trouble for your organization.

Disk Damage: If the disk is stalling for too long due to some kind of damage, it can greatly reduce performance. In cloud services for Oracle database, it translates into a broken DB instance that cuts access.

Broken Data: In case of a power outage, MySQL may fails to write data and close files as usual. There are also instances where MySQL fails to restart and doesn’t work despite the crash recovery process because of corruption in data.

Legislation/Regulation: Backups and recovery options ensure business value and client satisfaction.

Various Kinds of Backups for MySQL Database

Given below are some common backup categories that suit a range of needs:

Physical: These comprise the exact copies of database files and may contain part or all of the MySQL directory. The most common use of this type of backup is to make a new replica node and respond to host failure in a convenient manner. Experts recommend restoring data with the help of the same MySQL database version.

Offsite: This is one of the most recommended backup alternatives as it guarantees an untouched copy in case of data centre or host failure. It involves copying the data to the cloud, an external file server or another external source. However, sometimes it may take longer to download the files from the cloud or server than the recovery process. Therefore, experienced database professionals keep about a week of data locally on a backup server for quick recovery.

Logical: It is useful for smaller quantities of data as it is slower in comparison to physical backup methods. It essentially consists of dumps from INSERT and CREATE statements. It is useful in addressing data corruption or when you must recover a subset of tables. Although the output is greater in logical backups, especially when that data is present in text format, you can perform a quick compression if the software you’re using requires it. For instance, you can use Mydumper and mysqldump to compress and redirect the data to the zip folder.

Incremental: This type of backup contains all the changes made in the organization’s Oracle database and SQL server since the last backup. It is, therefore, quite useful for enormous datasets since it allows you to take small backups (experts recommend this after you’ve taken a full backup) as data comes later.

Differential: It consists of copying the modifications since your previous backup. One advantage of a differential backup is that it saves disk space. This is because the data in these backups mostly remains the same, so the result leads to backups that are substantially smaller in size.

improve performance of sql query

Every Oracle database admin dreads the day when they receive a flurry of complaint calls from users regarding slow online performance.

That’s why, if you’re responsible for managing database performance in your organization, you’ll want to ensure this doesn’t happen. How? By preparing your infrastructure to handle increased loads. Supporting it with performance tuning is also essential, especially when the systems slow down or become entirely unresponsive.

In this post, we’ll consider six important (yet often overlooked) methods and tips to improve Oracle database performance. These will also help you gain the most from your efforts and make sure your environment stays fully operational.

6 Ways to Optimize the Performance of Your Oracle Database

Take a look at the following tricks and tactics to improve Oracle database performance, explained in a simple manner: 

1. Maintain Optimum CPU Utilization Levels

It may be necessary to carry out manual tuning processes if, for some reason, you cannot apply the automatic diagnostic features Oracle provides. For this, you must make sure of complete CPU utilization in the user space. Check it to determine whether any non-database tasks are taking up CPU and restricting shared CPU resources.

2. Have a Firm Grasp of System Capabilities

Understanding the importance of baselines is essential to improve performance of SQL query. It helps to preserve a set performance baseline that you can refer to in case of performance issues.

You can do this by keeping an eye out for peak usage periods while measuring current performance. This will enable you to manage bottlenecks easily.

3. Make Use of an AWR (Automatic Workload Repository) Tool

An AWR is extremely useful as it gathers, processes, and maintains performance stats. It also provides a clear picture of your database’s health. The Automatic Database Diagnostic Monitor (ADDM) can help you gain actionable insights from the information you gain here. Together, these tools will save you time and money while enhancing the performance tuning process.

4. Tune Inefficient SQLs Using the Right Tools

The quickest and the least risky way to get rid of Oracle database problems is to tune the SQL using the right query plan. You can also use tuning tools for the Oracle database, such as those provided by Tosska Technologies Limited.

Tosska’s SQL Tuning Expert (TSE™) for Oracle® is ideal for all levels of experience and expertise. Its professional version, Tosska SQL Tuning Expert Pro (TSE Pro™) for Oracle®, can improve performance of SQL query with or without source code. However, these tools work best when you define and measure system issues correctly first.

5. Boost Storage Efficiency

It is possible to improve database performance by enhancing the performance of the storage platform. Review the existing storage for your Oracle database server and see if you can opt for alternatives.

For instance, flash technology offers considerably greater bandwidth and decreased latency to IO-bound workloads. It allows targeted provisioning, thereby boosting performance while eliminating the need to refresh the whole database. The key is to use flash storage for database objects that will benefit the most, leaving the rest in traditional storage.

6. Opt for a Dedicated Database Infrastructure

Sometimes, a common infrastructure platform can be the reason behind reduced performance results. No amount of tuning efforts proves sufficient in such cases. One of the most effective solutions is to provide a dedicated infrastructure to the database. This helps stabilize performance for database workloads and convenient management as well as effective monitoring and security. 

Ready to improve Oracle database performance in the simple ways mentioned above? You may choose to seek assistance from Tosska’s professional tuning tools for Oracle. They are designed to help you get the most out of your database and maintain a fully operational environment.

download free sql server

Click to view Tosska SQL Tuning Expert Pro (TSE Pro™) 4.4.0 Release Notes

optimization of SQL queries

If there is one complaint business users may have about their production database, it is slow performance. Database professionals, therefore, often try to focus strictly on finding out and resolving the source of the issue in the database.

The Database Engine Tuning Advisor (DTA) is one of the best tools in this regard. It helps DBAs analyze workloads and uncover areas that can be improved. In this blog, we will discuss the working of this tool along with a few additional details.

What is the Database Engine Tuning Advisor?

It is a tool that assists with the optimization of SQL queries and was introduced in SQL Server 2005. Before it, SQL Server had a feature known as the Index Tuning Wizard.

The DTA is designed to assess a workload and provide recommendations to boost query performance. Some of its suggestions include:

  • Making partitions
  • Incorporating indexes
  • Adding statistics (this helps resolve the issue of automatic statistics not getting created despite the auto_create_statistics option being ON)

Apart from locating every type of potential for enhancement, the Oracle Database Engine Tuning Advisor will build a T-SQL script for users to execute in order to carry out the recommendations made by it.

How to Launch the DTA for the Optimization of SQL Queries

You can commence its use through multiple methods:

  • Open the Start menu, scroll to the SQL Server application group and look for the Performance Tools folder.
  • If you’re using the SQL Server Management Studio application, you can select the tool from the Tools menu.
  • The SQL Server Profiler also has this tool in its Tools menu.
  • You can find it with the select analyze query in DTA on the SQL Server Management Studio Query menu. This also enables you to pass a T-SQL section to the tool for analysis.
  • Open the Command Prompt, type “DTA -?” for a glimpse at the available alternatives.

Normally, you can create a workload by collecting multiple statements in a file or with the help of the SQL Server Profiler. An important point to bear in mind is that the workload being sent to the Advisor for evaluation needs to be representative of the average workload.

What the Database Engine Tuning Advisor Does

The Database Engine Tuning Advisor makes recommendations on the basis of the workload you send for analysis. Therefore, a limited workload will result in inadequate recommendations. The best thing to do is to collect the workload through the Profiler, save the results in a text file, and send the trace to the Advisor.

The SQL Server Profiler plays an important role in the optimization of SQL queries. It can be launched from its location in the SQL Server application folder (in the Start menu) or among the list of tools in the SQL Server Management Studio.

In case you want to know the properties of the new trace, follow these steps –

  • Click on the dropdown list in the dropdown menu of the tool window (for the trace template) and select Tuning. The trace template gathers the events considered necessary by DTA.
  • Select the ‘Save to file’ and type in the file name you want before passing it to the Database Engine Tuning Advisor once the trace is complete.
SQL Server database and SQL

Choosing the right version of SQL Server is important for the performance you desire. If you’re installing an older one because your organization’s management prefers an older build or the vendor is unable to support newer versions, it is important to let them know which version your company needs, and why.

For this reason, we will discuss some popular versions of SQL Server from older to newer and mention their advantages in this blog.

Which SQL Server Version Works Best with SQL Performance Tuning?

Knowing the versions that support this task is extremely important because it will give you the ability to improve the SQL Server database and SQL performance.

To that effect, we will discuss the SQL Server 2016, 2017, and 2019 versions here.

SQL Server 2016

This version was chosen by a lot of independent software vendors or ISVs for one reason – 2016’s Service Pack 1 edition came with Enterprise features in Standard mode. These helped create a single application version that worked simultaneously for both Standard as well as Enterprise clients.

Advantages of Choosing this Version:

  • It is easy to find support material online as this version is quite popular and numerous database professionals are well-versed with this version’s tools.
  • Standard Edition users may find this version appealing since it supports 128GB RAM and additional space for internal functions such as query plans.
  • Support for this version ends after 2026 – longer than the older versions (2012/2014).
  • Newer applications that have additional compliance requirements will benefit from features in this version such as Always Encrypted, temporal tables, and Dynamic Data Masking. These will make it somewhat easier to protect and monitor sensitive information.
  • You can have both row store and column store indexes in this version, unlike the earlier ones that only had row store indexes.
  • If you need query plan monitoring to help with SQL performance tuning, you can use the Query Store’s features provided in SQL Server 2016 for this purpose.

SQL Server 2017

Being a newer release, it is one of the most regularly updated versions with patches coming in almost every other month. These patches are important because they resolve significant problems. It also comes with a minimum commit replica configuration to ensure commits are accepted by several replicas.

Advantages of Choosing this Version:

  • The upgrades are easier to get from this version onward due to a Distributed Availability Group that contains multiple SQL Server versions in it. Before this, we had AG version upgrades that were not as convenient, leading most users to construct a new cluster and migrate to it rather than opt for an upgrade.
  • This version contains batch mode execution plans, which gives those who require high-performance column store statements an advantage.
  • If you must run your SQL Server on Linux, you may consider SQL Server 2017 as several bugs have been resolved in the Cumulative Updates.
  • It’s a newer version so support will last longer than that of its predecessor.

SQL Server 2019

Released on November 4, 2019, this version is the latest in the SQL Server series. Naturally, it comes with the longest support lifespan, i.e. it will be supported until 2030. This version also receives regular patch updates to fix many significant issues in the form of Cumulative Updates.

Changes and Features in this Version:

  • Patch contents aren’t documented anymore. Moreover, you are likely to receive updates with undocumented new features – something to consider in case you require it for mission-critical production environments.
  • There is a bit of a learning curve thanks to some cutting-edge features in this version, so be prepared to perform some experimentation as you learn.
  • Some of the best performance features are included in the 2019 compatibility mode. However, you will have to keep a close eye on all SQL Server databases and SQL queries – even the ones running fast at present – as these will alter your current execution plans. In other words, you will have to test both slow and fast queries to make sure the slow ones speed up and the fast ones don’t fall behind in performance.
  • Table variables have gotten better in this version along with user-defined functions.
  • Additional features to watch out for including Big Data Clusters, Java support, and high container availability, so you may want to explore this version if you’re looking for perks like these in the SQL Server you want.

In Conclusion

At this point, SQL Server 2017 might seem like the best version to go with, thanks to a balance of features, stability, and support lifespan. Furthermore, you’ll receive plenty of help with SQL performance tuning – a lifesaver for overworked professionals who may not have the time or resources to upgrade every server every year.

MySQL database and SQL

Effective database management requires one or more tools regardless of the platform your databases run on. The benefit of these tools is, whether they are operating on Windows, macOS, Linux, or the cloud, the tools mentioned below don’t require the same platform as the databases. 

Thanks to plenty of choices when it comes to SQL management tools, it may seem difficult to select the ones that will work best as per your specific needs. In this blog, we’ve picked out the best paid and free SQL tools for Windows along with their essential features.

Free SQL Tools for Windows with a Graphical User Interface (GUI)

Consider the following free SQL tools for Windows to help you with efficient database management:

  1. SQL Server Data Tools (SSDT)

The SSDT is designed for a variety of databases such as Azure SQL, SQL Server relational databases, RS reports(Reporting Services), IS packages(Integration Services), and AS data models (Analysis Services). It is a development tool that allows users to create and implement any SQL Server content form with a convenience identical to that of Visual Studio.

  1. SQL Server Management Studio (SSMS)

The SQL Server Management Studio tool comes with an interactive Graphical User Interface that helps users control a SQL Server database or an instance. Users can gain access to any part of the SQL Server, Azure Synapse Analytics, or the Azure SQL Database and make changes, regulate, supervise, and develop them. 

You may want to look for this tool when you download free SQL Server as it also offers an all-encompassing utility which brings together a wide range of graphical tools along with several rich script editors. These are useful to DBAs and developers of varying skill levels.

  1. Visual Studio Code

The Visual Studio Code enables users to write T-SQL scripts using a compact editor. We are talking about the mssql extension – the official extension for Visual Studio Code that supports SQL Server linking and offers a productive T-SQL editing experience.

  1. Azure Data Studio

This is also a compact and handy editor capable of running SQL various functions including –

  • Executing SQL statements whenever required
  • Organizing preferred database connections
  • Viewing and storing results in text, JSON, or Excel format
  • Exploring database objects in a familiar environment
  • Editing information

Tosska’s Range of SQL Tuning & Query Optimizer Tools

Tosska Technologies offers several solutions to improve database performance through query optimization in SQL. With the goal of introducing new technologies that will help users overcome SQL-related obstacles, they provide a range of software designed using AI technology capable of solving a broad range of database performance issues.

Here’s what this range includes:

  • Tosska SQL Tuning Expert (TSES™) for SQL Server® – Unlike some of the free SQL tools for Windows, this is a powerful tool that doesn’t require professional expertise to tune your SQL queries. The AI engine does all the work, generating the most useful hints and alternate SQL statements that are semantically equivalent to the query that’s been entered to know whether there are better execution plans. You may pick the best option among the ones provided by the engine.
  • Tosska SQL Tuning Expert (TSEM™) for MySQL® – The TSEM™ comes with the A.I. capabilities of the TSE product range. However, this one-button-solution tool is tailored specifically for the MySQL database, tuning MySQL SQL queries without the users’ intervention. Users don’t have to perform manual rewriting or use the hit-and-trial method for each troublesome query, since it’s all handled by our embedded AI engine.
  • Tosska SQL Tuning Expert for Oracle® (TSE™ and TSE Pro™) version 4 – This tool comes with features exclusive to this family of tools, such as SQL rewrite, index exploration, and injecting Oracle hints to help tune SQL queries and boost their performance. It may or may not access your source code depending on the requirements, and the tool comes with a smart Indexes Advisor that offers cost-efficient indexes as per the workload. Make sure you get it when you download free tool and take advantage of this cutting-edge technology!
  • Tosska In-Memory Maestro (TIM™) for Oracle® – The TIM™ transforms the in-memory SQL optimization process into an automatic one and gives suggestions according to the SQL workload in question through our proprietary A.I. engine. It also offers a user-friendly simulation feature that virtually assesses table objects present in the memory for a SQL workload but doesn’t occupy those table objects.
SQL Server database and SQL

Bind Variables are typically considered as one of the major aspects of enhanced SQL query performance. According to Oracle documentation, they serve as a placeholder in a SQL query, getting replaced by a particular value that helps in statement execution.

The use of these variables enables users to create statements that can receive time-running parameters or inputs. One may think of bind variables as “value” given to the SQL query that acts as any function in programming languages. Here, we will talk more about them as well as their advantages and disadvantages in Oracle database and SQL.

Bind Variables: Examples of Their Uses

Consider the following statements in SQL –

Select * from Staff where S_No = 1 ;

Select * from Staff where S_No = :a ;

In the first query, a proper value (1) is applied to operate the query, whereas, in the next query, we have used a bind variable (:a) to operate the statement. This bind variable is given to Oracle when the query is run.

Defining a bind variable in the SQL statements in the place of literal values ensures that a single Parent Cursor is utilized by Oracle for the query. This helps improve database performance because Oracle searches for precise text matches for the query to check whether it already exists in the shared pool. Using a bind variable rather than a literal value saves an expensive hard parse for each run of that query.

Bind variables prove especially useful in OLTP-type environments because their use facilitates soft parsing. In other words, it takes less processing time to re-generate execution plan.

How Bind Variables Help Improve Database Performance

Given below are some advantages of using bind variables:

  1. Optimal Use of Shared Pool – The Shared Pool in Oracle Database needs to hold a single query instead of possibly numerous queries, thanks to bind variables.
  2. Improved Performance Due to Zero Hard Parsing – There is no need for hard parsing because SQL queries only diverge in terms of values.
  3. Decreased “library cache” Latch Contention – Since library cache latch contention is needed during a hard parse, its requirement reduces when bind variables are used.

Shortcomings of Bind Variables

The disadvantages of using bind variables are few. Although bind variables prove excellent if you want to improve Oracle database performance, there are instances where their use can negatively impact results:

  • They can decrease the flow of information needed to compute the best access path for CBO (Cost Based Optimizer). The CBO, in turn, may fail to identify the correct selectivity and create insufficient bad execution plans, opting for a complete table scan instead of using indexes.
  • Sometimes, the CBO requires the literal value to be used by SQL in order to build a robust execution plan. With bind variables, the literal value gets “hidden”, so the CBO is likely to create a subpar plan.

To overcome this issue, Oracle has tried to provide further assistance to the CBO by enabling it to take a look at the bind variable’s value during execution plan creation, which is known as “Bind Variable Peeking”.

Conclusion

The use of bind variables is extremely useful in Oracle database performance, especially when it comes to OLTP environments. However, as a user, you need to be careful while using bind variables. . It is recommended to use bind variables for short runtime SQL, but use literals for long time SQL statements to more information to CBO to generate good query plans.

TSE SQL Sever-09-r1

Click to view Tosska SQL Tuning Expert (TSES™) for SQL Server 1.5.0 Release Notes