A Beginners Guide To SQL. Master SQL Quickly

Learn to view data with SQL select statements by choosing specific columns from a table rather than using * and delimit field names with brackets or quotes when needed.

Master sorting data with the order by clause in SQL Server, ordering by surname, first name, or email, using ascending or descending and multi-column sorts, and converting data types.

Master sql quickly by learning to filter data with the where clause, compare text and numeric fields, and order results using practical examples like gender, name, and salary.

Learn to handle null or empty values in SQL by filtering for missing data and replacing nulls with defaults in select statements, using as for meaningful column aliases.

Save and comment SQL queries to reuse them later, using double hyphens for line comments and slash-star blocks to suppress code, while experimenting with where and order by clauses.

Master how to filter data with the where clause using wildcards across text, numeric, and time data, including like, not like, underscores, percentage signs, and square brackets.

Master multi-criteria SQL queries with and, or, and the IN clause to filter multiple values in one field or across fields, using parentheses to group conditions.

Learn to add a calculated column in SQL select by creating a new field from existing data, contact id times 1000 or salary times 0.2, with a runtime-only result.

Master text manipulation in sql with left, right, and substring functions to extract initials, postcodes, and email prefixes from text fields, using char index to locate separators across sql variants.

Explore six standard date functions that work across SQL Server, Access, and Oracle, and learn how to extract month, year, day, and weekday using datepart or prefixes.

Calculate age using date of birth and today's date, dividing days by 365.25 and applying floor to get whole years, adapting to database-specific date functions.

Learn how to concatenate data columns in SQL Server and Access, including adding spaces, using delimiters, and handling different data types with convert and format functions.

Explore how table relationships define primary keys and foreign keys, then join multiple tables with inner joins using on clauses and aliases to extract matching records from SQL Server databases.

Join more than two tables in SQL by defining relationships and on conditions, using aliases to combine contacts, marital status, and gender data.

Explore inner joins and left and right outer joins to combine related tables. Learn to show all left-side records and identify non-matching or orphan records with where clauses.

Explore the cross join, or cartesian join, which pairs every row from two tables when you omit join conditions, expanding results dramatically in SQL Server and Access.

Join multiple tables to summarize data with group by, count, and totals. Learn to group by marital status labels and by person, calculating totals across joined tables.

Learn how to amend data in tables with SQL update statements, using set, where, and optional filters to adjust salaries, update fields, and create identifiers via concatenation.

Learn how to insert data into tables with insert statements, including column lists, values, text and date delimiters, data types, and single-table inserts in sql server and access.

Use the delete statement to remove specific records with a where clause, or truncate to erase all data and reset identity counters, noting permanent deletion.

Create a new table with the create table syntax, define fields and data types, and use identity for auto increment in sql server, with notes on access differences.

Learn how to alter a table with the alter table command: add, drop, and modify columns, including changing a column's data type, with examples on the contact data table.

Learn how to create and use views in SQL Server to pre-compile complex queries, rename columns, join tables, and filter data for efficient, reusable data retrieval.

Learn how to alter, drop, and recreate views to update queries, add columns, and effectively rename by dropping the old view and creating a new one.

Compare the main variances in SQL between databases, focusing on semicolons, data types, delimiters, and functions. Learn what works where across SQL Server, Access, Oracle, and other packages.

Learn to use subqueries inside queries, filter towns with more than five occupants via in (subquery), and add a derived shares column through a subquery.

Explore core sql concepts from select, where, and joins to group by and aggregates, and learn to create, alter, drop tables, and update or delete data, with views and procedures.