Results for "Query Performance"
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Statistics in SQL Server
Statistics SQL Server ke “mind” jaise hote hain. Ye SQL Server ko batate hain ki table me data kis tarah se distribute hai — jaise kitne values unique hain…
SQL Server Deadlock & Performance Monitoring Made Easy
Learn how to detect SQL Server deadlocks and monitor performance with ready-to-use stored procedures for faster troubleshooting and optimization.
SQL Server Optimization Q&A
...wer: SQL Server Optimization ka matlab hota hai database ka performance better banana — jaise queries fast chalna, k…
SQL Interview Q&A
...he provided context: What is SQL? SQL stands for Structured Query Language. I…
SQL Server Index Optimization Automation (Missing & Unused Index Management)
Got it! Yeh lo plain content — seedha copy karo apne blog mein. Pehle workflow diagram, phir poora blog content.Pehle workflow diagram — screenshot leke blog m…
Understanding Locking Hints in SQL Server: NOLOCK, ROWLOCK, and UPDLOCK
What Are Locking Hints? Locking hints are special options you can include in your SQL queries to tell SQL Server how to handle locks on the data being quer…
In-Memory Databases (Data Warehouse Context)
🔹 In-Memory Database kya hoti hai? In-memory database wo database hoti hai jisme: 👉 Data hard disk par store nahi hota 👉 Data directly RAM (memory) me s…
What is an Index? Explain its different types in SQL
✅ Index in SQL Server (इंडेक्स इन SQL सर्वर): Index SQL Server में एक database object (डेटाबेस ऑब्जेक्ट) है जो टेबल के डेटा को जल्दी से प्राप्त करने के लिए…
Table Partitioning in SQL Server
Table Partitioning एक advanced database concept है जिसका उपयोग बड़े tables को छोटे, manageable हिस्सों (partitions) में बाँटने के लिए किया जाता है। इससे pe…
Logical Query Processing Phases in SQL
SQL query processing consists of several logical phases, which describe the order in which SQL statements are evaluated. These phases help in understanding…
TempDB in SQL Server
Introduction SQL Server me ek aisa database hai jo har query, har process aur almost har operation me involve hota hai. Ye ek temporary w…
What is Managed and External table in Spark
In Apache Spark, both Managed and External tables are used to store the data. However, there are significant differences in how Spark manages the data for …
Common Table Expressions (CTEs) in SQL
The Employee Hierarchy Problem Imagine you are working with an employee database where each employee might report to a manager. Here's a sample table struc…
Index Rebuilding vs. Reorganization in SQL Server
As a database grows, maintaining optimal performance becomes crucial. One of the key contributors to performance degradation over time is index fragmentati…
⭐ Star Schema vs ❄ Snowflake Schema – Data Warehouse Modeling
⭐ Star Schema Kya Hota Hai? Star Schema ek simple aur sabse popular data warehouse model hai. Isme: Beech me hoti hai 👉 Fact Table Uske around hoti hain �…
SQL Logical Operators with Examples
SQL logical operators are used to filter data by combining multiple conditions in SQL queries. These operators help in refining queries to fetch specific r…
ANY and ALL operators used in SQL
...a boolean value as a result returns TRUE if any of the sub-query values meet the condition Any means that the condition will be t…
PartitionBy() in PySpark
partitionBy() एक function है जो DataFrame को disk par likhne (write) के time par use hota hai. ये function pyspark.sql.DataFrameWriter class ka part hai. �…
JSON Data – Complete Conceptual Guide (SQL Server Perspective)
🔹 JSON kya hota hai? (Quick recap) JSON (JavaScript Object Notation) ek lightweight text format hota hai data exchange ke liye. Example: { "empId…
What is Blocking in SQL, How to solve blocking, and Kill Session
...is Blocking in SQL? Blocking occurs in SQL Server when one query or transaction holds a lock on a resource (like a row or table) and prevents other qu…
Understanding SQL Query for Identifying and Analyzing Default Values and Constraint in a Database
Default constraints in SQL are used to assign a default value to a column when no value is provided during data insertion. However, managing and auditing t…
XML Data – Complete Conceptual Guide (SQL Server Perspective)
How insert data on table from XML in SQL server, example: There are two method for insert data in table from XML. DECLARE @XMLInput VARCHAR(MAX); SET @XMLI…
Understanding Cursors in +SQL Server: A Complete Guide
When working with databases, most SQL operations are designed to handle large sets of data at once. However, there are cases where you may need to process …
What is a SQL Statement and types of SQL statements
A SQL (Structured Query Language) statement is a query or command used to perform various operations on data stored in a relational database. SQL statement…
Filtering the data with TOP and OFFSET-FETCH In SQL
TOP: SELECT TOP (5) productid, unitprice FROM Production.Products WHERE categoryid = 1 ORDER BY unitprice DESC; SELECT TOP (5) WITH TIES productid, unitpri…
Data Pipeline and ETL (Extract, Transform, Load) Process/Tool and ELT
The ETL (Extract, Transform, Load) process/tool to collect, clean, and store data in a structured format. Extract (निकालना): सबसे पहले, डेटा को विभिन्न स्र…
Working with Multiple Grouping Sets in SQL Server
...kground - क्यों ज़रूरत पड़ी GROUPING SETS की? जब हमें एक ही query में अलग-अलग तरीके से data को group करके summary चाहिए होती है, तब हम GROUPING SE…
Find column in the whole database in sql server
...pecific column in the whole database in SQL Server, you can query the information schema views. Here's a query you can use: SELECT table_name, c…
MSDB Database in SQL Server
SQL Server me ek aur powerful system database hai jo automation + scheduling ka backbone hai: MSDB Database
What is SQL and what is it used for?
SQL stands for Structured Query Language , and it is a standard programming language used for managing and manipulating data within relational databases. S…
SQL Server Management Studio (SSMS) – Complete Beginner Guide
SQL Server Management Studio Kya Hai? SQL Server Management Studio (SSMS) ek graphical interface (GUI tool) hai jisse aap SQL Server ke almost saare operat…
SQL Server Administration – Management Tools Overview
Is section me hum mainly SQL Server ke management tools aur system databases ko samjhenge. SQL Server Management Tools Jab aap Microsoft SQL Server install…
What is MPP (Massively Parallel Processing)
Aaj ke time me: ✔ Data bahut fast grow ho raha hai ✔ Users bahut zyada queries run kar rahe hain ✔ Reports real-time chahiye Traditional database model is …
Row-Based vs Column-Based (Columnar) Storage
Database me table hume: Rows aur columns ke form me dikhti hai. Lekin internally data store hone ka tareeka alag hota hai. Do main storage types hote hain:…
MDF, NDF, LDF, and Filegroups
🔹 1. Filegroup kya hota hai? 🔸 Definition: Filegroup SQL Server में logical storage unit hota hai, jisme ek ya zyada data files hoti hain. Ye filegroups …
What are Data warehouse, Data Lake ,data mining and DataMart and MetaData
Why a Data Warehouse? (Data Warehouse ki zarurat kyu hoti hai?) Aaj ke time me companies ka data multiple sources me store hota hai, jaise: • SQL Server da…
Understanding Stored Procedures in MSSQL
What is a Stored Procedure? A stored procedure is a group of SQL statements that are compiled and saved in the database. Instead of writing the same SQL qu…
Data archive in SQL Server
A data archive refers to the process of moving inactive or less frequently used data from an operational system to a storage system , typically in a separa…
Spark SQL useful command
Spark SQL provides a variety of commands for managing databases, tables, and performing SQL operations. CREATE DATABASE IF NOT EXISTS demo; SHOW DATABASES;…
Master Database in SQL Server
Introduction SQL Server me agar koi ek database sabse zyada critical hai, to wo hai: Master Database Ye SQL Server ka core brain hai. Agar master database …
SQL Server System Databases
Introduction SQL Server me jab hum kaam karte hain, to generally hum tables, queries aur user databases par focus karte hain. Lekin ek hidden backbone hota…
OLTP vs OLAP: A Beginner's Guide
What is OLTP? OLTP stands for Online Transaction Processing . It is a type of database system designed to handle a large number of short, quick operations,…
What are System Tables, File Tables, External Tables and Graph Tables in SQL Server
1. System Tables Definition : System tables are internal tables used by SQL Server to store information about the database and server itself. These are met…
Making API Calls in Python
APIs (Application Programming Interfaces) are the bridges that allow different software systems to communicate with each other. pip install requests import…
Basic of DAX query
// How to check null ISBLANK(EmployeeDetails[DateofLeaving]) //if condition IF(ISBLANK(EmployeeDetails[DateofLeaving]),TODAY(),EmployeeDetails�…
How to find table column information by using SQL query
Comprehensive Guide to Fetching Table and Column Metadata with SQL Server Stored Procedures When working with databases, understanding the structure of tab…
Window Aggregate Functions in SQL
What is window function: Imagine you have a dataset with many rows, and you want to perform some calculations on each row based on a group of rows related …
What difference between between MySQL and MSSQL
Feature MySQL MSSQL Ownership Oracle Corporation Microsoft Licensing Open-source (GPL) and commercial versions Commercial with free Express Edition Operati…
SQL Server Agent Alerts, Operators, Database Mail & Job Activity Monitor
Production environment me sirf jobs schedule karna hi kaafi nahi hota. Hume monitoring aur notification system bhi chahiye hota hai taaki agar koi job fail…
Data Warehouse and Data Mining Syllabus
Yeh Data Warehouse and Data Mining ka complete syllabus list format me diya hai, bina explanation ke — sirf topics list: PART 1: Data Warehouse Syllabus Li…
Database Shrink in SQL Server
Database shrink ka matlab hai database file (ya log file) ke size ko chhota karna by removing unused space . Matlab, agar tumhare DB me data delete ho gaya…
What is cluster in Spark
what is cluster : In computing, a cluster refers to a collection of interconnected computers that work together as a single system . These computers, often…
Schema and Handling Corrupt data in PySpark
A schema in PySpark (and generally in data processing) defines the structure of a DataFrame, including the names and data types of each column. It serves a…
SYS and INFORMATION_SCHEMA
sys In Microsoft SQL Server, the sys schema is a special schema that contains system views and stored procedures that provide metadata about the SQL Server…
Use of Apply(Cross and Outer) operator in SQL server
APPLY operator joins two table expressions. Also, I'll show how it differs from regular JOINs. Operator: CROSS APPLY Similar: INNER JOIN When to Use: Use a…
WAITFOR in sql server
...or wait period in the execution of a batch, transaction, or query. WAITFOR DELAY '00:00:05…
Comparison of WHERE Clause Operators in MSSQL vs PostgreSQL
Here's a comparison of how operators in the WHERE clause are used in Microsoft SQL Server (MSSQL) vs PostgreSQL : Operator Purpose Used in MSSQL Used in Po…
What is View in SQL server
A view is a virtual table based on the result-set of an SQL statement. A view contains rows and columns, just like a real table. IF OBJECT_ID('ViewTable','…
How to use GOTO statement in SQL server
If you want to jump to a specific point in your SQL code, you can use the GOTO statement. The GOTO statement is used to exit a loop or a nested block of co…
SQL Server Configuration Manager
Introduction Jab hum Microsoft SQL Server install karte hain , tab kuch important tools automatically install ho jate hain. Unme se ek bahut important tool…
Indexes in Data Warehouse
Database Me Data Kaise Store Hota Hai? Table ke rows disk par randomly store hote hain. Example: Row Customer_ID Sales 1 8 100 2 5 200 3 4 300 4 8 150 Agar…
Natural Key vs Surrogate Key in Data Warehouse
Dimensional Modeling me ek important topic hota hai: 👉 Natural Key 👉 Surrogate Key Dono primary key ke type hain, lekin inka purpose aur usage alag hota …
What Is Dimensional Modeling in Data Warehouse?
Before going deep into Star Schema and Fact Tables, pehle ek basic sawal: Dimensional Modeling hota kya hai? Dimensional Modeling ek technique hai jo Data …
What Are OLAP Cubes
When we work with a Data Warehouse, one common goal is fast reporting and analysis . Business users don’t want to wait 30 seconds for a dashboard to load. …
What is “CREATE TABLE TYPE” in SQL Server?
Ye ek User-Defined Table Type (UDTT) hota hai. Aap SQL Server me ek custom table ka design bana lete ho, jise aap baad me Stored Procedures, Functions, aur…
Advance Python Concept
The @property decorator in Python is used to make a method behave like an attribute . It allows you to define getters, setters, and deleters in an elegant …
What is the Replication in MS SQL server
Replication is a way to copy data from one database to another and keep them in sync. This is useful when you want the same data available in multiple plac…
What is Big Data
Big Data refers to extremely large datasets that are too complex and voluminous to be processed and analyzed using traditional data processing tools and te…
What is Data Ingestion and DataFrame API
Data ingestion : Data ingestion refers to the process of collecting, importing, and importing data from various sources into a system or storage environmen…
Triggers in SQL server
A trigger in SQL is a special type of stored procedure that runs automatically when certain actions happen in a table or view . A trigger cannot be explici…
SQL Server Multi-Level Approval Workflow with Auto Skip Logic
In many enterprise applications like HRMS, Travel Requests, Expense Approval, Purchase Approval , we need a multi-level approval workflow . But real system…
Model & Resource Database in SQL Server
Introduction SQL Server ke system databases me kuch aise hidden heroes hote hain jo directly dikhte nahi, lekin bahut powerful role play karte hain. Aaj hum 2…
Dynamic CREATE TABLE Script in SQL Server
DECLARE @TableName NVARCHAR(100) = 'Employee'; DECLARE @SQL NVARCHAR(MAX) = ''; DECLARE @PKCols NVARCHAR(MAX) = ''; -- Get Primary Key Column(s) SELECT @PK…
Table Types Comparison: SQL Server vs PostgreSQL
Table Type SQL Server PostgreSQL Scope / Lifetime Usage Notes Permanent Table CREATE TABLE Employee (...) CREATE TABLE Employee (...) Permanent in DB until…
Python String format()/f-string Method
Python में format() / f-string method का उपयोग Strings में वैल्यूज़ को dynamic तरीके से insert करने के लिए किया जाता है। यह एक बहुत ही powerful और readable…
Understanding DataFrames in PySpark
DataFrames are an important data structure in PySpark. They help in handling structured and semi-structured data efficiently. DataFrames are like tables in…
Data Import from text/CSV file in SQL Server
Step-by-Step Explanation 1. Checking and Dropping Existing Temporary Tables Before creating the temporary tables, the script ensures that any previously ex…
Database Permissions in SQL Server
In SQL Server, database permissions control what actions users can perform on specific database objects (like tables, views, and stored procedures). Permis…
Log Shipping (Ship Log) in SQL Server
Log Shipping in SQL Server is a high-availability feature that allows you to automatically send transaction log backups from a primary database on one serv…
Database Backup in SQL Server
In SQL Server, taking a database backup is crucial for data recovery and protection. Here’s a basic guide on how to perform a database backup and restore i…
Functions in MySQL
In MySQL, a Function is similar to a Stored Procedure but with some key differences. Functions are used to perform calculations or operations and return a …
What is Functions and Difference between Functions and Stored Procedures in SQL Server
What is a Function in sql : A function is a set of SQL Statements that perform a specific task. Basically, it is a set of SQL statements that accept only i…
Pivoting and Unpivoting Data in SQL
Pivoting Data : Pivoting is the process of converting rows of data into columns, effectively changing the orientation of your data. It's useful when you ha…
Spark session vs Spark context
In Apache Spark, SparkSession and SparkContext are both essential components, but they serve different purposes and have different scopes. Here's a detaile…
What is catalog in Spark
In Apache Spark, the catalog refers to the internal management system that keeps track of all the metadata related to tables, databases, functions, and oth…
Azure Databricks command
Here are some common commands used in Databricks: %fs : Allows you to interact with the filesystem. For example, %fs ls lists the files in the current dire…
Databricks, Apache Spark, Data Engineering and Science etc.
Azure Databricks is a platform on Microsoft Azure that helps with big data analysis and machine learning. It lets you work with large datasets easily and c…
Implementing Transactions,Error Handling, and Dynamic SQL in SQL
Think of a transaction as a complete package deal. It's like when you buy something from a store. You give them money, and in return, you expect to get the…
How to comma separate value by using XML in SQL server
Before SQL Server 2017 (14.x), you can achieve the comma-separated values using the XML method. Here's an example of how you can achieve this: DECLARE @Sta…