1. Open Firefox and click on the menu icon:
+
Use the "customize" option to find the SQLite Manager Plugin:
+
You can add it to your menu by dragging or right-click to add it to the toolbar.
+2. Create a new database called campaign_finance:
+
3. Create a new table called contributions (
) and give it the following field definitions:
4. Insert a row of data.
+Use the "Execute SQL" tab (it's in the second menu row, under the icons)
+
And paste or type the following statement:
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name, city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','BUFFETT','WARREN','','OMAHA','Nebraska','68131','BERKSHIRE HATHAWAY','CHAIRMAN','2015-04-15',2700);5. Insert three more rows (one at a time or all at once)
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00577130','IND','RUFFALO','MARK','','NEW YORK','NY','|100031526','SELF-EMPLOYED','ACTOR','2015-06-02',250);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00458844','IND','ADELSON','SHELDON','','LAS VEGAS','NV','89145','','','2015-06-12',2600);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00579458','IND','MANNING','PEYTON MR.','','CLEVELAND','OH','441141717','DENVER BRONCOS','PROFESSIONAL ATHLETE','2015-08-04',2700);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','COPPOLA','SOFIA','','NEW YORK','NY','100130778','SELF-EMPLOYED','DIRECTOR/WRITER/ACTOR','2016-01-22',2700);6. Select everything from the contributions table:
+SELECT * FROM contributions;Note the wildcard * character.
+7. Choose some fields to select:
+SELECT city, state FROM contributions;Note the duplicates; why are they there?
+8. Get a distinct set of cities and states:
+SELECT DISTINCT city, state FROM contributions;9. Add some conditions to the SELECT:
+SELECT * from contributions WHERE state='NY';Now try playing around with some of the operators:
+| operator | +description | +
| = | +Equal | +
| <> | +Not equal* | +
| > | +Greater than | +
| < | +Less than | +
| >= | +Greater than or equal | +
| <= | +Less than or equal | +
Here are some examples:
+SELECT * from contributions WHERE amount > 500;SELECT * from contributions WHERE amount >= 500;SELECT last_name from contributions WHERE state <> 'NY';10. Combine conditions with AND or OR:
+Find only the big spenders from New York
+SELECT * FROM contributions WHERE city = 'NEW YORK' AND amount > 2000;Find any big spender and anyone from New York
+SELECT * FROM contributions WHERE city = 'NEW YORK' OR amount > 2000;11. But watch out for operator precedence
+Looking for big spenders from Las Vegas and New York City
+SELECT * FROM contributions WHERE city = 'NEW YORK' OR city = 'LAS VEGAS' AND amount > 2000;How did Mark Ruffalo sneak in there?
+Try that again:
+SELECT * FROM contributions WHERE (city = 'NEW YORK' OR city = 'LAS VEGAS') AND amount > 2000;BETWEEN and IN (NOT IN)11. Find all contributions between $500 and $1000
+SELECT * FROM contributions WHERE amount BETWEEN 251 AND 2699;(Note: this query returns the same results as SELECT * FROM contributors WHERE amount >= 500 AND amount <= 1000; -- but it's much more readable.)
12. Find all contributors from a list of states:
+SELECT * from contributions WHERE state IN ('OH', 'NY');(Note: A compound statement could accomplish this same goal: state = 'OH' OR state = 'NY'
+But the IN syntax makes things much clearer, and it's easier to write.)
13. Use NOT IN to find results where a value is not included in the given set:
SELECT * FROM contributions WHERE state NOT IN ('NY', 'OH');14. Use ORDER BY to sort:
+SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount;And reverse the order:
+SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount DESC;And order by more than one column:
+SELECT state, last_name, amount FROM contributions ORDER BY state, amount DESC;15. Return only the top two contributions:
+SELECT * FROM contributions ORDER BY amount DESC LIMIT 2;16. Check the list of state names again:
+SELECT state FROM contributions;Let's correct Nebraska:
+UPDATE contributions SET state = 'NE' WHERE state = 'Nebraska';And check again:
+SELECT DISTINCT state FROM contributions;17. Let's get rid of a row:
+SELECT * FROM contributions WHERE id = 1;DELETE FROM contributions WHERE id = 1;18. Import a delimited file:
+a. Go to https://raw.githubusercontent.com/tthibo/SQL-Tutorial/master/NICAR2016/part1/data/contributions.txt (Or grab it from the conference computer.)
b. Save the file as "contributions.txt" somewhere you can find it (your desktop is a good place).
+c. Click the SQLite Manager Import Wizard icon (
).
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name, city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','BUFFETT','WARREN','','OMAHA','Nebraska','68131','BERKSHIRE HATHAWAY','CHAIRMAN','2015-04-15',2700);
+
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00577130','IND','RUFFALO','MARK','','NEW YORK','NY','|100031526','SELF-EMPLOYED','ACTOR','2015-06-02',250);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00458844','IND','ADELSON','SHELDON','','LAS VEGAS','NV','89145','','','2015-06-12',2600);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00579458','IND','MANNING','PEYTON MR.','','CLEVELAND','OH','441141717','DENVER BRONCOS','PROFESSIONAL ATHLETE','2015-08-04',2700);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','COPPOLA','SOFIA','','NEW YORK','NY','100130778','SELF-EMPLOYED','DIRECTOR/WRITER/ACTOR','2016-01-22',2700);
+SELECT * FROM contributions;SELECT city, state FROM contributions;SELECT DISTINCT city, state FROM contributions;SELECT * from contributions WHERE state='NY';SELECT * from contributions WHERE amount > 500;SELECT * from contributions WHERE amount >= 500;SELECT last_name from contributions WHERE state <> 'NY';SELECT * FROM contributions WHERE city = 'NEW YORK' AND amount > 2000;SELECT * FROM contributions WHERE city = 'NEW YORK' OR amount > 2000;SELECT * FROM contributions WHERE city = 'NEW YORK' OR city = 'LAS VEGAS' AND amount > 2000;SELECT * FROM contributions WHERE (city = 'NEW YORK' OR city = 'LAS VEGAS') AND amount > 2000;BETWEEN and IN (NOT IN)
+
+11. Find all contributions between $500 and $1000
+SELECT * FROM contributions WHERE amount BETWEEN 251 AND 2699;SELECT * FROM contributors WHERE amount >= 500 AND amount <= 1000; -- but it's much more readable.)
+
+SELECT * from contributions WHERE state IN ('OH', 'NY');state = 'OH' OR state = 'NY'
+But the IN syntax makes things much clearer, and it's easier to write.)
+
+NOT IN to find results where a value is not included in the given set:
+SELECT * FROM contributions WHERE state NOT IN ('NY', 'OH');SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount;SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount DESC;SELECT state, last_name, amount FROM contributions ORDER BY state, amount DESC;SELECT * FROM contributions ORDER BY amount DESC LIMIT 2;SELECT state FROM contributions;UPDATE contributions SET state = 'NE' WHERE state = 'Nebraska';SELECT DISTINCT state FROM contributions;SELECT * FROM contributions WHERE id = 1;DELETE FROM contributions WHERE id = 1;
+CREATE TABLE "contributions" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "entity_type" VARCHAR,
+ "last_name" VARCHAR,
+ "first_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "city" VARCHAR,
+ "state" VARCHAR,
+ "zip_code" VARCHAR,
+ "employer" VARCHAR,
+ "occupation" VARCHAR,
+ "date" DATETIME,
+ "amount" INTEGER,
+ "candidate_id" INTEGER NOT NULL,
+ FOREIGN KEY(candidate_id) REFERENCES candidates(id)
+);
+
+SELECT COUNT(id) FROM contributions WHERE state = 'CA';SELECT MAX(amount) FROM contributions;SELECT MIN(amount) FROM contributions;SELECT SUM(amount) FROM contributions WHERE state = 'GA';SELECT AVG(amount) FROM contributions;SELECT state, SUM(amount) FROM contributions GROUP BY state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state ORDER BY SUM(amount) DESC;
+
+CREATE TABLE "candidates" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "first_name" VARCHAR,
+ "last_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "party" VARCHAR
+);
+
+
+
+SELECT MAX(amount) FROM contributions;
+
+Then SELECT all fields for any contribution at that amount . . . but how?
+
+Like this?
+SELECT * FROM contributions WHERE amount = MAX(amount);
+
+Nope.
+
+Hardcode the amount?
+SELECT * FROM contributions WHERE amount = 5400;SELECT * FROM contributions WHERE amount = (SELECT MAX(amount) FROM contributions);SELECT SUM(amount) FROM contributions WHERE id IN (SELECT id FROM contributions ORDER BY amount DESC LIMIT 20);SELECT * FROM contributions WHERE candidate_id = (SELECT id from candidates WHERE last_name = 'CLINTON' AND first_name = 'HILLARY');WHERE clause:
+
+SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions, candidates WHERE contributions.candidate_id = candidates.id;SELECT a.last_name, a.first_name, b.last_name FROM contributions a, candidates b WHERE a.candidate_id = b.id;JOIN syntax
+
+18. Rewrite the above query using explicit JOIN syntax:
+SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions JOIN candidates ON contributions.candidate_id = candidates.id;JOIN syntax:
+SELECT a.last_name, a.first_name, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id;SELECT count(a.id), b.id, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;SELECT DISTINCT id, last_name FROM candidates;JOIN returns the same results as the query with this clause: WHERE contributions.candidate_id = candidates.id.
+
+What if a candidate has no contributions? Then that candidate is not returned by the query.
+
+The JOIN acts just like the WHERE clause and filters out any rows that don't match the condition defined.
+
+Joins that return only rows in which there is a match in both tables are known as *INNER JOINs*. This is often exactly the behavior you want from the join (ignore any rows from either table that don't relate to a row in the other table). So by default, the JOIN keyword executes an INNER JOIN. You can also explicitly request an INNER JOIN, just to make things clearer:
+
+SELECT count(a.id), b.id, b.last_name FROM contributions a INNER JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;LEFT OUTER JOIN includes all rows from the table on the left side of the statement and only matching rows from the table on the right side of the statement.
+* A RIGHT OUTER JOIN includes all rows from the table on the right side of the statement and only matching rows from the left side of the statement.
+* A FULL OUTER JOIN includes all rows from both tables.
+
+Currently, SQLite only supports LEFT OUTER JOIN from the list above, but some other database management systems support the other two types as well.
+
+15. Get the number of contributions for each candidate, including those with no contributions:
+
+SELECT candidates.last_name, count(contributions.id)
+FROM candidates LEFT OUTER JOIN contributions
+ON candidates.id = contributions.candidate_id
+GROUP BY candidates.id, candidates.last_name
+ORDER BY count(contributions.id);
+
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00494740','IND','BUFFETT','WARREN','OMAHA','Nebraska','68131','BERKSHIRE HATHAWAY/CHAIRMAN','CHAIRMAN','2500');
+
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00494740','IND','WINFREY','OPRAH','CHICAGO','IL','60607','HARPO INC.','CHAIRMAN/CEO',500);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00494740','IND','PRITZKER','PENNY S','CHICAGO','IL','60614','HYATT','EXEC',2500);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00431171','IND','ADELSON','SHELDON','LAS VEGAS','NV','89109','VENETIAN HOTEL','OWNER','2500');
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00431171','IND','MARRIOTT','BILL MR. JR.','BETHESDA','MD','20817','MARRIOTT INTERNATINAL INC.','CHAIRMAN & C.E.O.','587');
+SELECT * FROM contributions;SELECT city, state FROM contributions;SELECT DISTINCT city, state FROM contributions;SELECT * from contributions WHERE state='IL';SELECT * from contributions WHERE amount > 500;SELECT * from contributions WHERE amount >= 500;SELECT last_name from contributions WHERE state <> 'IL';SELECT * FROM contributions WHERE state = 'IL' AND amount > 2000;SELECT * FROM contributions WHERE state = 'IL' OR amount > 2000;SELECT * FROM contributions WHERE city = 'CHICAGO' OR state = 'NV' AND amount > 2000;SELECT * FROM contributions WHERE (city = 'CHICAGO' OR state = 'NV') AND amount > 2000;SELECT last_name, amount FROM contributions WHERE amount > 200 ORDER BY amount;SELECT last_name, amount FROM contributions WHERE amount > 200 ORDER BY amount DESC;SELECT last_name, state, amount FROM contributions ORDER BY state, amount DESC;SELECT * FROM CONTRIBUTIONS ORDER BY amount DESC LIMIT 2;SELECT state FROM contributions;UPDATE contributions SET state = 'NE' WHERE state = 'Nebraska';SELECT DISTINCT state FROM contributions;SELECT * FROM contributions WHERE id = 1;DELETE FROM contributions WHERE id = 1;
CREATE TABLE "contributions" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "committee_id" VARCHAR,
+"entity_type" VARCHAR, "last_name" VARCHAR, "first_name" VARCHAR, "city" VARCHAR, "state" VARCHAR, "zip_code" VARCHAR,
+"employer" VARCHAR, "occupation" VARCHAR, "amount" INTEGER)
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00494740','IND','WINFREY','OPRAH','CHICAGO','IL','60607','HARPO INC.','CHAIRMAN/CEO',500);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00494740','IND','PRITZKER','PENNY S','CHICAGO','IL','60614','HYATT','EXEC',2500);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00431171','IND','ADELSON','SHELDON','LAS VEGAS','NV','89109','VENETIAN HOTEL','OWNER','2500');
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, city, state, zip_code, employer, occupation, amount) VALUES ('C00431171','IND','MARRIOTT','BILL MR. JR.','BETHESDA','MD','20817','MARRIOTT INTERNATINAL INC.','CHAIRMAN & C.E.O.','587');
+SELECT * FROM contributions WHERE amount BETWEEN 500 AND 1000;SELECT * FROM contributions WHERE state IN ('AL', 'GA', 'FL');SELECT * FROM contributions WHERE state NOT IN ('CA', 'OR', 'AZ');SELECT DISTINCT city, state, zip_code FROM contributions WHERE city = 'NEW YORK' AND state = 'NY' ORDER BY zip_code;SELECT zip_code FROM contributions WHERE zip_code = '10017';SELECT zip_code FROM contributions WHERE zip_code LIKE '10017%';SELECT * FROM contributions WHERE first_name LIKE '% _.%'; SELECT first_name, last_name FROM contributions WHERE state = 'NH';SELECT * FROM contributions WHERE last_name IS NULL;SELECT * FROM contributions WHERE state = 'NH';SELECT * FROM contributions WHERE state = 'NH' AND last_name <> 'BAKER';SELECT * FROM contributions WHERE state = 'NH' AND (last_name <> 'BAKER' OR last_name IS NULL);SELECT * FROM contributions WHERE state = 'NH' AND last_name IS NOT NULL;UPDATE contributions SET state = ' IL ' WHERE last_name = 'WINFREY';SELECT DISTINCT state FROM contributions ORDER BY state;UPDATE contributions SET state = TRIM(state);SELECT city, state FROM contributions WHERE state = 'AL' ORDER BY city, state;SELECT * FROM contributions WHERE state = 'AL' AND city = 'BIRMINGHAM';SELECT * from contributions WHERE state = 'AL' AND UPPER(city) = 'BIRMINGHAM';SELECT DISTINCT city, state, zip_code FROM contributions WHERE city = 'NEW YORK' AND state = 'NY' ORDER BY zip_code;SELECT SUBSTR(zip_code, 1, 5) FROM contributions;SELECT COUNT(id) FROM contributions WHERE state = 'CA';SELECT COUNT(DISTINCT zip_code) FROM contributions;SELECT COUNT(DISTINCT state) FROM contributions;SELECT MAX(amount) FROM contributions;SELECT MIN(amount) FROM contributions;SELECT AVG(amount) FROM contributions;SELECT SUM(amount) FROM contributions WHERE state = 'GA';SELECT state, SUM(amount) FROM contributions GROUP BY state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state ORDER BY SUM(amount) DESC;SELECT * FROM contributions WHERE amount = MAX(amount);SELECT MAX(amount) FROM contributions;SELECT * FROM contributions WHERE amount = 5000;SELECT * FROM contributions WHERE amount = (SELECT MAX(amount) FROM contributions);SELECT SUM(amount) FROM contributions WHERE id IN (SELECT id FROM contributions ORDER BY amount DESC LIMIT 20);SELECT state, SUM(amount) FROM contributions GROUP BY state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state ORDER BY SUM(amount) DESC;SELECT city, state, SUM(amount) FROM contributions GROUP BY state ORDER BY SUM(amount) DESC;SELECT city, state, SUM(amount) FROM contributions WHERE SUM(amount) >= 3000 GROUP BY city, state ORDER BY SUM(amount) DESC;SELECT city, state, SUM(amount) FROM contributions GROUP BY city, state HAVING SUM(amount) >= 10000 ORDER BY SUM(amount) DESC;SELECT city, state, amount FROM contributions WHERE amount >= 2300;SELECT city, state, SUM(amount) FROM contributions WHERE amount >= 2300 GROUP BY city, state;SELECT city, state, SUM(amount) FROM contributions WHERE amount >= 2300 GROUP BY city, state HAVING SUM(amount) > 10000;1. Open Firefox and click on the menu icon:
+
Use the "customize" option to find the SQLite Manager Plugin:
+
You can add it to your menu by dragging or right-click to add it to the toolbar.
+2. Create a new database called campaign_finance:
+
3. Create a new table called contributions () and give it the following field definitions:
4. Insert a row of data.
+Use the "Execute SQL" tab (it's in the second menu row, under the icons)
+
And paste or type the following statement:
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name, city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','BUFFETT','WARREN','','OMAHA','Nebraska','68131','BERKSHIRE HATHAWAY','CHAIRMAN','2015-04-15',2700);5. Insert three more rows (one at a time or all at once)
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00577130','IND','RUFFALO','MARK','','NEW YORK','NY','|100031526','SELF-EMPLOYED','ACTOR','2015-06-02',250);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00458844','IND','ADELSON','SHELDON','','LAS VEGAS','NV','89145','','','2015-06-12',2600);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00579458','IND','MANNING','PEYTON MR.','','CLEVELAND','OH','441141717','DENVER BRONCOS','PROFESSIONAL ATHLETE','2015-08-04',2700);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','COPPOLA','SOFIA','','NEW YORK','NY','100130778','SELF-EMPLOYED','DIRECTOR/WRITER/ACTOR','2016-01-22',2700);6. Select everything from the contributions table:
+SELECT * FROM contributions;Note the wildcard * character.
+7. Choose some fields to select:
+SELECT city, state FROM contributions;Note the duplicates; why are they there?
+8. Get a distinct set of cities and states:
+SELECT DISTINCT city, state FROM contributions;9. Add some conditions to the SELECT:
+SELECT * from contributions WHERE state='NY';Now try playing around with some of the operators:
+| operator | +description | +
| = | +Equal | +
| <> | +Not equal* | +
| > | +Greater than | +
| < | +Less than | +
| >= | +Greater than or equal | +
| <= | +Less than or equal | +
Here are some examples:
+SELECT * from contributions WHERE amount > 500;SELECT * from contributions WHERE amount >= 500;SELECT last_name from contributions WHERE state <> 'NY';10. Combine conditions with AND or OR:
+Find only the big spenders from New York
+SELECT * FROM contributions WHERE city = 'NEW YORK' AND amount > 2000;Find any big spender and anyone from New York
+SELECT * FROM contributions WHERE city = 'NEW YORK' OR amount > 2000;11. But watch out for operator precedence
+Looking for big spenders from Las Vegas and New York City
+SELECT * FROM contributions WHERE city = 'NEW YORK' OR city = 'LAS VEGAS' AND amount > 2000;How did Mark Ruffalo sneak in there?
+Try that again:
+SELECT * FROM contributions WHERE (city = 'NEW YORK' OR city = 'LAS VEGAS') AND amount > 2000;BETWEEN and IN (NOT IN)11. Find all contributions between $500 and $1000
+SELECT * FROM contributions WHERE amount BETWEEN 251 AND 2699;(Note: this query returns the same results as SELECT * FROM contributors WHERE amount >= 500 AND amount <= 1000; -- but it's much more readable.)
12. Find all contributors from a list of states:
+SELECT * from contributions WHERE state IN ('OH', 'NY');(Note: A compound statement could accomplish this same goal: state = 'OH' OR state = 'NY'
+But the IN syntax makes things much clearer, and it's easier to write.)
13. Use NOT IN to find results where a value is not included in the given set:
SELECT * FROM contributions WHERE state NOT IN ('NY', 'OH');14. Use ORDER BY to sort:
+SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount;And reverse the order:
+SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount DESC;And order by more than one column:
+SELECT state, last_name, amount FROM contributions ORDER BY state, amount DESC;15. Return only the top two contributions:
+SELECT * FROM contributions ORDER BY amount DESC LIMIT 2;16. Check the list of state names again:
+SELECT state FROM contributions;Let's correct Nebraska:
+UPDATE contributions SET state = 'NE' WHERE state = 'Nebraska';And check again:
+SELECT DISTINCT state FROM contributions;17. Let's get rid of a row:
+SELECT * FROM contributions WHERE id = 1;DELETE FROM contributions WHERE id = 1;18. Import a delimited file:
+a. Go to https://raw.githubusercontent.com/tthibo/SQL-Tutorial/master/NICAR2016/part1/data/contributions.txt (Or grab it from the conference computer.)
b. Save the file as "contributions.txt" somewhere you can find it (your desktop is a good place).
+c. Click the SQLite Manager Import Wizard icon ().
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name, city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','BUFFETT','WARREN','','OMAHA','Nebraska','68131','BERKSHIRE HATHAWAY','CHAIRMAN','2015-04-15',2700);
+
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00577130','IND','RUFFALO','MARK','','NEW YORK','NY','|100031526','SELF-EMPLOYED','ACTOR','2015-06-02',250);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00458844','IND','ADELSON','SHELDON','','LAS VEGAS','NV','89145','','','2015-06-12',2600);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00579458','IND','MANNING','PEYTON MR.','','CLEVELAND','OH','441141717','DENVER BRONCOS','PROFESSIONAL ATHLETE','2015-08-04',2700);
+INSERT INTO contributions (committee_id, entity_type, last_name, first_name, middle_name,city, state, zip_code, employer, occupation, date, amount) VALUES ('C00575795','IND','COPPOLA','SOFIA','','NEW YORK','NY','100130778','SELF-EMPLOYED','DIRECTOR/WRITER/ACTOR','2016-01-22',2700);
+SELECT * FROM contributions;SELECT city, state FROM contributions;SELECT DISTINCT city, state FROM contributions;SELECT * from contributions WHERE state='NY';SELECT * from contributions WHERE amount > 500;SELECT * from contributions WHERE amount >= 500;SELECT last_name from contributions WHERE state <> 'NY';SELECT * FROM contributions WHERE city = 'NEW YORK' AND amount > 2000;SELECT * FROM contributions WHERE city = 'NEW YORK' OR amount > 2000;SELECT * FROM contributions WHERE city = 'NEW YORK' OR city = 'LAS VEGAS' AND amount > 2000;SELECT * FROM contributions WHERE (city = 'NEW YORK' OR city = 'LAS VEGAS') AND amount > 2000;BETWEEN and IN (NOT IN)
+
+11. Find all contributions between $500 and $1000
+SELECT * FROM contributions WHERE amount BETWEEN 251 AND 2699;SELECT * FROM contributors WHERE amount >= 500 AND amount <= 1000; -- but it's much more readable.)
+
+SELECT * from contributions WHERE state IN ('OH', 'NY');state = 'OH' OR state = 'NY'
+But the IN syntax makes things much clearer, and it's easier to write.)
+
+NOT IN to find results where a value is not included in the given set:
+SELECT * FROM contributions WHERE state NOT IN ('NY', 'OH');SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount;SELECT last_name, amount FROM contributions WHERE amount > 250 ORDER BY amount DESC;SELECT state, last_name, amount FROM contributions ORDER BY state, amount DESC;SELECT * FROM contributions ORDER BY amount DESC LIMIT 2;SELECT state FROM contributions;UPDATE contributions SET state = 'NE' WHERE state = 'Nebraska';SELECT DISTINCT state FROM contributions;SELECT * FROM contributions WHERE id = 1;DELETE FROM contributions WHERE id = 1;1. Open Firefox and the SQLite Manager Plugin
+
2. Create a new database called contributions_candidates
+
3. Use a CREATE TABLE statement to create a new table for candidate data:
+
+CREATE TABLE "candidates" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "first_name" VARCHAR,
+ "last_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "party" VARCHAR
+);
+4. Use the SQLite Manager Import Wizard () to import candidates.txt
Remember to select the pipe delimiter ("|") and to check the box indicating that the first row contains headers.
+ +5. Use a CREATE TABLE statement to create a new contributions table:
+CREATE TABLE "contributions" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "entity_type" VARCHAR,
+ "last_name" VARCHAR,
+ "first_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "city" VARCHAR,
+ "state" VARCHAR,
+ "zip_code" VARCHAR,
+ "employer" VARCHAR,
+ "occupation" VARCHAR,
+ "date" DATETIME,
+ "amount" INTEGER,
+ "candidate_id" INTEGER NOT NULL,
+ FOREIGN KEY(candidate_id) REFERENCES candidates(id)
+);
+6. Use the SQLite Manager Import Wizard () to import contributions.txt:
7. Find out the maxiumum contribution amount in the data set and see which contributors have given this amount.
+First, determine the maximum amount contriubuted:
+SELECT MAX (amount) FROM contributions;
Then SELECT all fields for any contribution at that amount . . . but how?
+Like this?
+SELECT * FROM contributions WHERE amount = MAX (amount);
Nope.
+Hardcode the amount?
+SELECT * FROM contributions WHERE amount = 5400;But what if next month the max changes? How can we make this dynamic?
+Subqueries to the rescue:
+SELECT * FROM contributions WHERE amount = (SELECT MAX(amount) FROM contributions);8. Write a query that gets the sum amount of the top 20 contributions
+SELECT SUM(amount) FROM contributions WHERE id IN (SELECT id FROM contributions ORDER BY amount DESC LIMIT 20);9. Find all of the contributions to Hillary Clinton
+SELECT * FROM contributions WHERE candidate_id = (SELECT id from candidates WHERE last_name = 'CLINTON' AND first_name = 'HILLARY');10. It is possible to do an implicit join simply by defining the relationship between the two tables in the WHERE clause:
SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions, candidates WHERE contributions.candidate_id = candidates.id;11. Use table name aliases to save typing:
+SELECT a.last_name, a.first_name, b.last_name FROM contributions a, candidates b WHERE a.candidate_id = b.id;This query returns the same results as the one above, but it saves some typing by making "a" an alias for "contributions" and "b" an alias for "candidates." The alias can use any valid table name you
+like, but obviously shorter aliases will save more typing, while longer ones may make the intention of the query easier to understand.
JOIN syntax12. Rewrite the above query using explicit JOIN syntax:
+SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions JOIN candidates ON contributions.candidate_id = candidates.id;13. Use aliases work with JOIN syntax:
SELECT a.last_name, a.first_name, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id;14. Get the number of contributions for each candidate
+SELECT count(a.id), b.id, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;Our list of candidates seems to be coming up short. Let's check it:
+SELECT DISTINCT id, last_name FROM candidates;Definitely missing candidates. What happened?
+Performing the JOIN returns the same results as the query with this clause: WHERE contributions.candidate_id = candidates.id.
What if a candidate has no contributions? Then that candidate is not returned by the query.
+The JOIN acts just like the WHERE clause and filters out any rows that don't match the condition defined.
Joins that return only rows in which there is a match in both tables are known as INNER JOINs. This is often exactly the behavior you want from the join (ignore any rows from either table that don't relate to a row in the other table). So by default, the JOIN keyword executes an INNER JOIN. You can also explicitly request an INNER JOIN, just to make things clearer:
SELECT count(a.id), b.id, b.last_name FROM contributions a INNER JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;The results will be the same.
+LEFT OUTER JOIN includes all rows from the table on the left side of the statement and only matching rows from the table on the right side of the statement.RIGHT OUTER JOIN includes all rows from the table on the right side of the statement and only matching rows from the left side of the statement.FULL OUTER JOIN includes all rows from both tables.Currently, SQLite only supports LEFT OUTER JOIN from the list above, but some other database management systems support the other two types as well.
15. Get the number of contributions for each candidate, including those with no contributions:
+SELECT candidates.last_name, count(contributions.id)
+FROM candidates LEFT OUTER JOIN contributions
+ON candidates.id = contributions.candidate_id
+GROUP BY candidates.id, candidates.last_name
+ORDER BY count(contributions.id);(Note: Aliases would work here as well.)
diff --git a/NICAR2016/part3/part3_steps.textile b/NICAR2016/part3/part3_steps.textile new file mode 100644 index 0000000..274149b --- /dev/null +++ b/NICAR2016/part3/part3_steps.textile @@ -0,0 +1,175 @@ +h2. SQLite III: Subqueries and Joins in SQLite + +1. Open Firefox and the SQLite Manager Plugin +!./images/ff-menu.png! + +
+
+CREATE TABLE "candidates" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "first_name" VARCHAR,
+ "last_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "party" VARCHAR
+);
+
+
+
+
+CREATE TABLE "contributions" (
+ "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,
+ "committee_id" VARCHAR,
+ "entity_type" VARCHAR,
+ "last_name" VARCHAR,
+ "first_name" VARCHAR,
+ "middle_name" VARCHAR,
+ "city" VARCHAR,
+ "state" VARCHAR,
+ "zip_code" VARCHAR,
+ "employer" VARCHAR,
+ "occupation" VARCHAR,
+ "date" DATETIME,
+ "amount" INTEGER,
+ "candidate_id" INTEGER NOT NULL,
+ FOREIGN KEY(candidate_id) REFERENCES candidates(id)
+);
+
+SELECT MAX(amount) FROM contributions;
+
+Then SELECT all fields for any contribution at that amount . . . but how?
+
+Like this?
+SELECT * FROM contributions WHERE amount = MAX(amount);
+
+Nope.
+
+Hardcode the amount?
+SELECT * FROM contributions WHERE amount = 5400;SELECT * FROM contributions WHERE amount = (SELECT MAX(amount) FROM contributions);SELECT SUM(amount) FROM contributions WHERE id IN (SELECT id FROM contributions ORDER BY amount DESC LIMIT 20);SELECT * FROM contributions WHERE candidate_id = (SELECT id from candidates WHERE last_name = 'CLINTON' AND first_name = 'HILLARY');WHERE clause:
+
+SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions, candidates WHERE contributions.candidate_id = candidates.id;SELECT a.last_name, a.first_name, b.last_name FROM contributions a, candidates b WHERE a.candidate_id = b.id;JOIN syntax
+
+12. Rewrite the above query using explicit JOIN syntax:
+SELECT contributions.last_name, contributions.first_name, candidates.last_name FROM contributions JOIN candidates ON contributions.candidate_id = candidates.id;JOIN syntax:
+SELECT a.last_name, a.first_name, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id;SELECT count(a.id), b.id, b.last_name FROM contributions a JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;SELECT DISTINCT id, last_name FROM candidates;JOIN returns the same results as the query with this clause: WHERE contributions.candidate_id = candidates.id.
+
+What if a candidate has no contributions? Then that candidate is not returned by the query.
+
+The JOIN acts just like the WHERE clause and filters out any rows that don't match the condition defined.
+
+Joins that return only rows in which there is a match in both tables are known as *INNER JOINs*. This is often exactly the behavior you want from the join (ignore any rows from either table that don't relate to a row in the other table). So by default, the JOIN keyword executes an INNER JOIN. You can also explicitly request an INNER JOIN, just to make things clearer:
+
+SELECT count(a.id), b.id, b.last_name FROM contributions a INNER JOIN candidates b ON a.candidate_id = b.id GROUP BY b.id, b.last_name;LEFT OUTER JOIN includes all rows from the table on the left side of the statement and only matching rows from the table on the right side of the statement.
+* A RIGHT OUTER JOIN includes all rows from the table on the right side of the statement and only matching rows from the left side of the statement.
+* A FULL OUTER JOIN includes all rows from both tables.
+
+Currently, SQLite only supports LEFT OUTER JOIN from the list above, but some other database management systems support the other two types as well.
+
+15. Get the number of contributions for each candidate, including those with no contributions:
+
+SELECT candidates.last_name, count(contributions.id)
+FROM candidates LEFT OUTER JOIN contributions
+ON candidates.id = contributions.candidate_id
+GROUP BY candidates.id, candidates.last_name
+ORDER BY count(contributions.id);
+SELECT a.last_name, a.first_name, a.amount, b.amount FROM a, b WHERE a.last_name = b.last_name AND a.first_name = b.first_name;SELECT a.last_name, a.first_name, a.amount, b.amount FROM contributors_a a, contributors_b b WHERE a.last_name = b.last_name AND a.first_name = b.first_name;