One of the first steps in data analysis is examining data through aggregations. This chapter explores how to create aggregations in SQL Server, a common first step in data exploration. You will also clean missing data and categorize data into bins with CASE statements.

Data analysis with aggregations

Creating aggregations

Creating grouped aggregations

Dealing with missing data

Removing missing values

Imputing missing values (I)

Imputing missing values (II)

Binning data with CASE

Using CASE statements

Creating several groups with CASE

Summarizing Data

This chapter explores essential math operations such as rounding numbers, calculating squares and square roots, and counting records. You will also work with dates in this chapter! 

Counting and totals

Calculating the total

Counting the number of rows

Dates

Which date function should you use?

Counting the number of days between dates

Adding days to a date

Rounding and truncating

Rounding numbers

Truncating numbers

More math functions

Calculating the absolute value

Calculating squares and square roots

Math Functions

In this chapter, you will create variables and write while loops to process data. You will also write complex queries by using derived tables and common table expressions. 

Cicli WHILE

Creare e usare variabili

Creare un ciclo WHILE

Tabelle derivate

Query con tabelle derivate (I)

Query con tabelle derivate (II)

Common Table Expressions (CTE)

Sintassi delle CTE

Creare CTE (I)

Creare CTE (II)

Processing Data in SQL Server

In the final chapter of this course, you will work with partitions of data and window functions to calculate several summary stats and see how easy it is to create running totals and compute the mode of numeric columns.

Window functions in T-SQL

Window functions with aggregations (I)

Window functions with aggregations (II)

Common window functions

Do you know window functions?

First value in a window

Previous and next values

Increasing window complexity

Creating running totals

Assigning row numbers

Using windows for statistical functions

Calculating standard deviation

Calculating mode (I)

Calculating mode (II)

Window Functions

Incidents

Shipments

Kidney

Orders

La maggior parte dei dati è archiviata in database e conoscere gli strumenti necessari per analizzare e ripulire i dati direttamente nei database è indispensabile. Questo corso è incentrato su T-SQL, la versione di SQL usata in Microsoft SQL Server, necessaria per l’analisi dei dati. In questo corso imparerai vari concetti, come la gestione dei dati mancanti, il lavoro con le date e il calcolo di statistiche riepilogative usando query avanzate. Al termine, avrai le competenze per analizzare i dati e ottenere insight in modo rapido e semplice.

Introduction to SQL Server

Impara i concetti di T-SQL: gestire dati mancanti, lavorare con date e calcolare statistiche avanzate.

SQL Server intermedio

In questo corso userai T-SQL, il tipo di SQL che si usa in SQL Server di Microsoft per analizzare i dati.

Sviluppatore SQL Server

Fondamenti di SQL Server

Sintassi delle CTE

SQL Server intermedio

Esercizio pratico interattivo