ACID Properties & Normalization in SQLBy Sahil Ambardar | Last updated on March 5, 2025 | 87513 Views Previous Next ACID Properties ACID Property is the most important part of the database. ACID stands for Atom
This means all your non-key information must not be tied to another non-key column in your database table. Generally, this means you have to go over your data to see if there is anything that should be split off into its own table. This extra information tends to be data you need to...
First Normal Form (1NF) means that the table has no repeating groups, that is, every column is a scalar value and not an array or a list or anything with its own structure. In SQL, it is impossible not to be in 1NF unless the vendor has added an array or other extensions to the ...
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Even though you could just hold the Zip code (and house number) in ther UK on the customer record that then means that every time you would need to use the address you would have to look it up. This would be labourious and prone to issues, in the UK certainly new postcodes are con...
An entity is in a second normal form if all of its attributes depend on the whole primary key. So this means that the values in the different columns have a dependency on the other columns. The table must be already in 1 NF and all non-key columns of the tables must depend on the ...
Sometimes the database design that looks Ok at first sight may have some hidden problems. One such kind of problem is Non-Atomic Values. This means that the value that stored in a single column in the database is actually a combination of multiple values
It can be done onany relational database, where data is stored in tables that are linked to each other. This means that normalization in a DBMS (Database Management System) can be done in Oracle, Microsoft SQL Server, MySQL, PostgreSQL and any other type of database. ...
this approach hazardous. Moreover, constraints introduce atrade-off, speeding up reads (SELECTin SQL) while slowing down writes (INSERT,UPDATE, andDELETE). This means a denormalized database under heavy write load may actually offerworseperformance than its functionally equivalent normalized counterpart...
The primary key provides a means to uniquely identify each row in a table. When we talk about columns depending on the primary key, we mean, that to find a particular value, such as what color is Kris’ hair, you would first have to know the primary key, such as an EmployeeID, to...