Storage
What is Persistence?
Watch the presentation Se presentationen på svenska Persistence in data management refers to the capability of data to be stored in a non-volatile medium, allowing it to survive beyond the lifespan of the process that created it. Simply put, persistence ensures that data remains intact and accessible even after an application or system that generated it has stopped running or encountered failure. Key Aspects of Persistence Persistence is characterized by several important aspects: »
Databases
Watch the presentation Se presentationen på svenska A database is a structured collection of data stored and organized to facilitate easy access, retrieval, and management. Databases are crucial to the operation of almost all digital systems, from websites and mobile apps to complex business applications and enterprise software. They provide a reliable way to store vast amounts of data while supporting efficient processing and analysis, enabling organizations to handle transactions, generate reports, and make informed decisions. »
Storage
Watch the presentation Se presentationen på svenska Storage refers to the systems and devices used to save, retrieve, and manage data. It is ensuring that data remains persistently available for various purposes, including running applications, storing files, and maintaining databases. Storage solutions cater to a wide range of needs, from personal file storage on laptops to large-scale data storage in enterprises and cloud environments. Key Characteristics of Storage Storage solutions have several critical characteristics: »
Databaser
Vad är en Databas? Lagrar strukturerad data (ex. tabeller, dokument, tidsserier). Gör det möjligt att söka i data (ex. SQL Structured Query Language). Upprätthåller dataintegritet (ex. Primary keys, foreign keys, not null, unique, 1->n, n->n) Typer av Databaser Relationsdatabaser Använder tabeller med rader och kolumner (t.ex. MySQL, PostgreSQL). Structured Query Language (SQL) för datamanipulation. Typer av Databaser NoSQL-databaser Designade för semistrukturerad data (t.ex. MongoDB, DynamoDB). Flexibla scheman för olika datatyper (dokument, key-value) Typer av Databaser In-Memory-databaser »
Databases
What is a Database? A structured collection of data stored electronically. Enables efficient storage, retrieval, and management of information. Types of Databases Relational Databases: Use tables with rows and columns (e.g., MySQL, PostgreSQL). Structured Query Language (SQL) for data manipulation. NoSQL Databases: Designed for unstructured or semi-structured data (e.g., MongoDB, DynamoDB). Flexible schemas for diverse data types. In-Memory Databases: Store data in RAM for high-speed access (e.g., Redis, Memcached). Key Concepts Schema: Defines the structure of data in a database. »
Lagring
Vad är Lagring? Lagring avser system och enheter som används för att spara, hämta och hantera data. Karakteristik för lagring Kapacitet Den totala mängden data ett lagringssystem kan hantera. Mäts i GB, TB eller PB för större system. Prestanda Throughput: Mängden data som överförs per sekund (t.ex. MB/s). Latens: Tid det tar att få åtkomst till data efter en begäran. Karakteristik för lagring Redundans Replikerar data för att kunna återställa vid fel. »
Storage
What is Storage? Refers to saving and accessing data for future use. Critical for applications, systems, and data-driven operations. Types of Storage Block Storage: Divides data into fixed-sized blocks. Used for databases and applications (e.g., AWS EBS, Azure Disk Storage). File Storage: Organizes data in a hierarchical structure with files and folders. Ideal for shared access (e.g., NFS, SMB). Object Storage: Stores data as objects with metadata and unique IDs. Suitable for unstructured data (e. »
Vad är Persistens?
Vad är persistens? Data som lagras över tid på ett permanent lagringsmedium (non-volatile). Klarar strömavbrott. Data finns kvar även efter att applikationen som skapat det inte finns kvar Medium för persistens HDD - Hard Disk Drives (magnetskiva) SSD - Solid State Disk (flash-minne, inga rörliga delar) Optiska Medium (CD, DVD) Magnetband (oftast för backup) Molnlagring (Amazon S3, Azure Blob Storage) Typer av persistens Block Storage: För filsystem. Hårddiskar eller SAN (iSCSI) File Storage: Hanterar filer och kataloger likt ett filsystem. »
What is Persistence?
What is Persistence? The ability of a system to retain data over time. Essential for applications that require data storage and retrieval. Types of Persistence Volatile Storage: Temporary storage (e.g., RAM). Data is lost when power is off. Non-Volatile Storage: Permanent storage (e.g., HDD, SSD). Data persists even after power loss. Persistence in Computing Databases: Store structured data for easy access and manipulation. File Systems: Manage files on disk for long-term storage. »