published solutions

demo-queries-from slides-1.sql

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+--A SELECT statement that retrieves all the data from the Invoices table
+SELECT * FROM invoices;
+
+--A SELECT statement that retrieves three columns from each row, sorted in descending sequence by invoice total
+SELECT invoice_number, invoice_date, invoice_total
+FROM invoices
+ORDER BY invoice_total DESC;
+ 
+--A SELECT statement that retrieves two columns and a calculated value for a specific invoice
+SELECT invoice_id, invoice_total,
+       credit_total + payment_total AS total_credits
+FROM invoices
+WHERE invoice_id = 17;
+ 
+--A SELECT statement that retrieves two columns and a calculated value for a specific invoice
+SELECT invoice_number, invoice_date, invoice_total
+FROM invoices
+WHERE invoice_date BETWEEN '2018-06-01' AND '2018-06-30'
+ORDER BY invoice_date;
+ 
+--A SELECT statement that retrieves two columns and a calculated value for a specific invoice
+SELECT invoice_number, invoice_date, invoice_total
+FROM invoices
+WHERE invoice_total > 50000;

demo-queries-from slides-10.sql

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+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY vendor_name;
+
+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY vendor_name DESC;
+
+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY vendor_state, vendor_city, vendor_name;

demo-queries-from slides-11.sql

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+—An ORDER BY clause that uses an alias
+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY address, vendor_name;
+
+—An ORDER BY clause that uses an expression
+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY CONCAT(vendor_contact_last_name, vendor_contact_first_name);
+
+—An ORDER BY clause that uses column positions 
+SELECT vendor_name,
+  CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) AS address
+FROM vendors
+ORDER BY 2, 1;

demo-queries-from slides-12.sql

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+SELECT vendor_id, invoice_total
+FROM invoices
+ORDER BY invoice_total DESC
+LIMIT 5;
+
+SELECT invoice_id, vendor_id, invoice_total
+FROM invoices
+ORDER BY invoice_id
+LIMIT 2, 3;
+
+SELECT invoice_id, vendor_id, invoice_total
+FROM invoices
+ORDER BY invoice_id
+LIMIT 100, 1000;

demo-queries-from slides-2.sql

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+--A SELECT statement that renames the columns in the result se
+SELECT invoice_number AS "Invoice Number", invoice_date AS Date,
+       invoice_total AS Total
+FROM invoices;
+
+--A SELECT statement that renames the columns in the result se
+SELECT invoice_number, invoice_date, invoice_total,
+       invoice_total - payment_total - credit_total
+FROM invoices;
+

demo-queries-from slides-3.sql

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+--A SELECT statement that calculates the balance due 
+SELECT invoice_total, payment_total, credit_total,
+       invoice_total - payment_total - credit_total AS balance_due
+FROM invoices;
+
+
+--Use parentheses to control the sequence of operations
+SELECT invoice_id, 
+       invoice_id + 7 * 3 AS multiply_first, 
+       (invoice_id + 7) * 3 AS add_first
+FROM invoices
+ORDER BY invoice_id;
+
+--Use the DIV and modulo operators
+SELECT invoice_id, 
+       invoice_id / 3 AS decimal_quotient,
+       invoice_id DIV 3 AS integer_quotient,
+       invoice_id % 3 AS remainder
+FROM invoices
+ORDER BY invoice_id;

demo-queries-from slides-4.sql

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+--How to concatenate string data
+SELECT vendor_city, vendor_state, CONCAT(vendor_city, vendor_state)
+FROM vendors;
+
+--How to format string data using literal values
+SELECT vendor_name,
+       CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) 
+           AS address
+FROM vendors;
+
+--How to include apostrophes in literal values 
+SELECT CONCAT(vendor_name, '''s Address: ') AS Vendor,
+       CONCAT(vendor_city, ', ', vendor_state, ' ', vendor_zip_code) 
+           AS Address
+FROM vendors;
+

demo-queries-from slides-5.sql

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+
+--A SELECT statement that uses the LEFT function 
+SELECT vendor_contact_first_name, vendor_contact_last_name,
+       CONCAT(LEFT(vendor_contact_first_name, 1), 
+              LEFT(vendor_contact_last_name, 1)) AS initials
+FROM vendors;
+
+--A SELECT statement that uses the DATE_FORMAT function 
+SELECT invoice_date,
+       DATE_FORMAT(invoice_date, '%m/%d/%y') AS 'MM/DD/YY',
+       DATE_FORMAT(invoice_date, '%e-%b-%Y') AS 'DD-Mon-YYYY'
+FROM invoices
+ORDER BY invoice_date;
+
+--A SELECT statement that uses the ROUND function
+SELECT invoice_date, invoice_total,
+       ROUND(invoice_total) AS nearest_dollar,
+       ROUND(invoice_total, 1) AS nearest_dime
+FROM invoices
+ORDER BY invoice_date;
+

demo-queries-from slides-6.sql

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+--Four SELECT statements without FROM clauses 
+
+--Example 1: Testing a calculation
+SELECT 1000 * (1 + .1) AS "10% More Than 1000";
+
+--Example 2: Testing the CONCAT function
+SELECT "Ed" AS first_name, "Williams" AS last_name,
+    CONCAT(LEFT("Ed", 1), LEFT("Williams", 1)) AS initials;
+    
+--Example 3: Testing the DATE_FORMAT function 
+SELECT DATE_FORMAT(CURRENT_DATE, '%m/%d/%y') AS 'MM/DD/YY',
+       DATE_FORMAT(CURRENT_DATE, '%e-%b-%Y') AS 'DD-Mon-YYYY';
+
+--Example 4: Testing the ROUND function
+SELECT 12345.6789 AS value,
+       ROUND(12345.67) AS nearest_dollar,
+       ROUND(12345.67, 1) AS nearest_dime;

demo-queries-from slides-7.sql

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+--A SELECT statement that returns all rows
+SELECT vendor_city, vendor_state
+FROM vendors
+ORDER BY vendor_city;
+
+--A SELECT statement that eliminates duplicate rows
+SELECT DISTINCT vendor_city, vendor_state
+FROM vendors
+ORDER BY vendor_city;

demo-queries-from slides-8.sql

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+—-A compound condition without parenthese
+SELECT invoice_number, invoice_date, invoice_total, 
+(invoice_total - payment_total - credit_total) AS balance_due
+FROM invoices
+WHERE invoice_date > '2014-07-03' OR invoice_total > 500
+  AND invoice_total - payment_total - credit_total > 0;  
+  
+—The same compound condition with parentheses
+SELECT invoice_number, invoice_date, invoice_total, 
+(invoice_total - payment_total - credit_total) AS balance_due
+FROM invoices
+WHERE (invoice_date > '2014-07-03' OR invoice_total > 500)
+  AND invoice_total - payment_total - credit_total > 0;

demo-queries-from slides-9.sql

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+USE ex;
+
+SELECT * FROM null_sample;
+
+SELECT * FROM null_sample
+WHERE invoice_total = 0;
+
+SELECT * FROM null_sample
+WHERE invoice_total <> 0;
+
+SELECT * FROM null_sample
+WHERE invoice_total IS NULL;
+
+SELECT * 
+FROM null_sample
+WHERE invoice_total IS NOT NULL;