structured query language sql or sql for short is the gold standard language for communicating with relational database management systems you've likely heard of databases like mysql postgres microsoft sql server and oracle all of which are based on sql with their own little variations it was initially developed in the early 70s to mutate and retrieve data from ibm's system r database by 1986 it was standardized into the syntax that remains extremely popular in technical applications today a relational database organizes data into tables kind of like an excel spreadsheet where columns contain attributes or types of data while each row represents an individual record or data point with its own unique id known as a primary key we can establish relationships between data points by taking the unique id from one row and storing it on a different row in a different table in a special column known as a foreign key in the teams table the team id is the primary key but in the players table it's the foreign key and what that data structure tells us is that a player belongs to one team while a team can have many players what we've done here is structured our data in its smallest normal form to eliminate duplication and redundancy now the role of sql is not only to read create update and delete data but also to join data together based on the relationships embedded within it the syntax is comprised of several key parts if we zoom all the way out we have a statement or a piece of code that does something like reads or writes to the database within a statement we have a variety of keywords that can manipulate the database select can be used to make a query for the columns that you want from a table the column and table names are known as identifiers but we may not want every row in the table so we filter the results with the where keyword to only include records that meet a certain condition it's like looping over every row in the table and only returning rows in the query where the predicate evaluates to true then we might use the join keyword to connect data from an entirely different table by matching the primary key on this table to the foreign key on another table what we've created is a collection of clauses that make up a full sql statement we can now go and execute this code on the hundreds of different databases that support sql this has been structured query language in 100 seconds like and subscribe if you want to see a full sql tutorial thanks for watching and i will see you in the next one