Author: Abhishek Yadav
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Out of Memory Killer in Linux OS
In Linux systems, MySQL generally has a concept called Out of Memory killer OOM controlled by the kernel. This is to prevent the possible runaway process in OS to avoid race conditions and a server crash. Since MySQL and its optimized memory buffers are memory hogs, the OS may often kill the mysqld process to…
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DBA Worries Continued DBMS Concepts L1 DBA My SQL MySQL Architecture MySQL Basics MySQL L1 SQL Server
Deterministic and Nondeterministic Functions
Deterministic functions: Deterministic functions always result in the same output every time they are called with a fixed set of input values and given the same condition of the database. For example, AVG() function always results the same result given the qualifications stated above. Nondeterministic functions: Nondeterministic functions result in different output each time they…
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Fragmentation
Hey guys, In this blog I am going to explain you about Fragmentation and its types and how to detect fragmentation and fix it. SQL Server index fragmentation is a common source of database performance degradation. Fragmentation occurs when there is a lot of empty space on a data page (internal fragmentation) or when the logical…
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SQL Interview Questions
You can benefit from this article’s popular SQL Server DBA interview questions and answers. To learn more about SQL interview questions, I would advise you to read this post as well as the SQL Server Interview questions and answers. I made an effort to be very specific in my responses to each question in this…
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All about tempDB
Hey guys, In this blog I am going to explain you about TempDB TempDB is a workhorse of SQL Server performing a number of functions to support both system and internal operations. With this workload TempDB will process a large number of database writes, which requires low-latency, high throughput underlying storage. What about tempDB Size? It…
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PostgreSQL Index and Types
Hey guys, In this blog I am going to explain you about PostgreSQL Index and Types. PostgreSQL Index- The database search engine can use indexes, which are specialized lookup tables, to speed up data retrieval. An index is simply a pointer to information in a table. An index in a database resembles a book’s back…
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SQL Server’s in-memory OLTP technology
Hey guys, In this blog I am going to explain you about SQL Server’s in-memory OLTP technology. Introduction- A native stored procedure compiler and specialized, memory-optimized relational data management engine are both built into SQL Server as part of In-Memory OLTP. For the most demanding OLTP workloads, Microsoft created In-Memory OLTP. In many instances, the…
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SQL DBA Hand Book
Performance Monitoring Scan SQL Server Error Log Database Maintenance Missing Indexes in a DB Transaction Space Utilization Info SQL Server Statistics DB Backup and Restore History AAOG Log Sync Analysis Important SQL Server Scripts… Read a big file using PowerShell All about tempDB
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Index in MySQL
Index Info… SELECT DISTINCT TABLE_NAME, INDEX_NAME,COLUMN_NAME, index_type FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA =’thinklouder_optimization’; SHOW INDEXES FROM table_name IN database_name; —————————————————— OPTIMIZE TABLE tbl; will rebuild the indexes and do ANALYZE; it takes time. —————————————————— ANALYZE TABLE tbl; is fast for InnoDB to rebuild the stats. With 5.6.6 it is even less needed. —————————————————— Read the…
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IO Subsystem Analysis
SQLIO.exe is a tool provided by Microsoft that can be used to determine the I/O capacity of a given configuration. Installation:-> Step 1. Configure Param.txt The first step is to modify the file param.txt to tell SQLIO where to find its test file which is named testfile.dat. Parameter Description Values file name Name of the test file R:\testfile.dat number…
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Read a big file using PowerShell
# Command-Format: Get-Content ‘your-file-path’ -Tail <number-of-line>Get-Content ‘.\mylargefile.txt’ -Tail 5000 # Get-Content D:\MyBigFeedFile.txt | Select-Object -skip 123798766555672 -first 6
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Win OS Related Quick Commands
Find Who Restarted Windows Server –Run the following command to filter the System Logs with Source as User32. Get-EventLog -LogName System | Where Source -eq User32 –You may also filter the system logs with Event ID 1074 with the following command. Get-EventLog -LogName System | Where EventID -eq 1074
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