SQL built-in functions(aggregate,scalar)

SQL has many built-in functions for performing calculations on data.

SQL Aggregate Functions

SQL aggregate functions return a single value, calculated from values in a column.

Useful aggregate functions:

•    AVG() - Returns the average value

•    COUNT() - Returns the number of rows

•    FIRST() - Returns the first value

•    LAST() - Returns the last value

•    MAX() - Returns the largest value

•    MIN() - Returns the smallest value

•    SUM() - Returns the sum

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SQL Scalar functions

SQL scalar functions return a single value, based on the input value.

Useful scalar functions:

•    UCASE() - Converts a field to upper case

•    LCASE() - Converts a field to lower case

•    MID() - Extract characters from a text field

•    LEN() - Returns the length of a text field

•    ROUND() - Rounds a numeric field to the number of decimals specified

•    NOW() - Returns the current system date and time

•    FORMAT() - Formats how a field is to be displayed