Add first lecture SQL examples

.gitignore

@@ -67,6 +67,9 @@ web_modules/
 # Optional REPL history
 .node_repl_history
 
+# Editor swap files
+.*.kate-swp
+
 # Output of 'npm pack'
 *.tgz
 
@@ -129,4 +132,3 @@ dist
 .yarn/build-state.yml
 .yarn/install-state.gz
 .pnp.*
-

Lecture_1/01-bankovnictvi-import.sql

@@ -0,0 +1,148 @@
+-- Demo banking schema used by the first lecture.
+-- The accounts_clients table models a many-to-many relationship between clients and accounts.
+-- TABLES
+CREATE TABLE banks (
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    name VARCHAR(100) NOT NULL,
+    code VARCHAR(10) NOT NULL UNIQUE
+);
+
+CREATE TABLE clients (
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    name VARCHAR(100) NOT NULL,
+    email VARCHAR(255) NOT NULL UNIQUE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE accounts (
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    bank_id BIGINT NOT NULL,
+    account_number VARCHAR(50) NOT NULL UNIQUE,
+    balance NUMERIC(12,2) DEFAULT 0,
+    currency VARCHAR(10) NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (bank_id) REFERENCES banks(id)
+);
+
+CREATE TABLE accounts_clients (
+    client_id BIGINT NOT NULL,
+    account_id BIGINT NOT NULL,
+    PRIMARY KEY (client_id, account_id),
+    FOREIGN KEY (client_id) REFERENCES clients(id) ON DELETE CASCADE,
+    FOREIGN KEY (account_id) REFERENCES accounts(id) ON DELETE CASCADE
+);
+
+CREATE TABLE cards (
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    account_id BIGINT NOT NULL,
+    client_id BIGINT NOT NULL,
+    card_number VARCHAR(30) NOT NULL UNIQUE,
+    expiration DATE NOT NULL,
+    cvv VARCHAR(4) NOT NULL,
+    type VARCHAR(20) NOT NULL,
+    FOREIGN KEY (account_id) REFERENCES accounts(id) ON DELETE CASCADE,
+    FOREIGN KEY (client_id) REFERENCES clients(id) ON DELETE CASCADE
+);
+
+
+-- INSERTS
+-- Seed data intentionally mixes banks, currencies, shared accounts, and cards for SELECT exercises.
+INSERT INTO banks (name, code) VALUES
+('Ceska sporitelna', '0800'),
+('CSOB', '0300'),
+('Komercni banka', '0100'),
+('Moneta', '0600'),
+('Fio banka', '2010');
+
+INSERT INTO clients (name, email) VALUES
+('Jan Novak', 'jan.novak1@mail.cz'),
+('Petr Svoboda', 'petr.svoboda@mail.cz'),
+('Karel Dvorak', 'karel.dvorak@mail.cz'),
+('Martin Vesely', 'martin.vesely@mail.cz'),
+('Tomas Prochazka', 'tomas.prochazka@mail.cz'),
+('Jakub Horak', 'jakub.horak@mail.cz'),
+('Filip Cerny', 'filip.cerny@mail.cz'),
+('Adam Kriz', 'adam.kriz@mail.cz'),
+('Lukas Malek', 'lukas.malek@mail.cz'),
+('Ondrej Novak', 'ondrej.novak@mail.cz'),
+('David Ruzicka', 'david.ruzicka@mail.cz'),
+('Radek Fiala', 'radek.fiala@mail.cz');
+
+INSERT INTO accounts (bank_id, account_number, balance, currency) VALUES
+(1, '100001/0800', 15000.00, 'CZK'),
+(1, '100002/0800', 250.50, 'CZK'),
+(1, '100003/0800', 88.50, 'CZK'),
+(1, '100004/0800', 3200.00, 'USD'),
+(2, '200001/0300', 99999.99, 'CZK'),
+(2, '200002/0300', 1200.00, 'EUR'),
+(2, '200003/0300', 15000.00, 'USD'),
+(3, '300001/0100', 5400.00, 'CZK'),
+(3, '300002/0100', 780.00, 'CZK'),
+(3, '300003/0100', 780.00, 'USD'),
+(4, '400001/0600', 300.00, 'CZK'),
+(4, '400002/0600', 45000.00, 'CZK'),
+(4, '400003/0600', 19546.00, 'CZK'),
+(4, '400004/0600', 0.00, 'USD'),
+(5, '500001/2010', 999.00, 'EUR'),
+(5, '500002/2010', 123456.78, 'CZK'),
+(5, '500003/2010', 250.00, 'USD');
+
+
+
+
+
+INSERT INTO accounts_clients (client_id, account_id) VALUES
+(1, 1),
+(1, 2),
+(1, 13),
+(2, 1),
+(2, 3),
+(2, 14),
+(3, 3),
+(3, 4),
+(3, 11),
+(3, 15),
+(4, 4),
+(4, 5),
+(4, 16),
+(5, 5),
+(5, 6),
+(5, 17),
+(6, 6),
+(6, 7),
+(7, 7),
+(7, 8),
+(8, 8),
+(8, 9),
+(9, 9),
+(9, 10),
+(10, 10),
+(10, 12),
+(11, 1),
+(12, 2),
+(12, 3);
+
+
+
+INSERT INTO cards (account_id, client_id, card_number, expiration, cvv, type) VALUES
+(1, 1, '1111222233334441', '2028-12-31', '123', 'debit'),
+(1, 2, '1111222233334442', '2027-11-30', '234', 'credit'),
+(2, 1, '1111222233334451', '2026-10-31', '345', 'debit'),
+(3, 2, '1111222233334461', '2029-09-30', '456', 'credit'),
+(3, 3, '1111222233334462', '2027-08-31', '567', 'debit'),
+(4, 3, '1111222233334471', '2028-07-31', '678', 'debit'),
+(5, 4, '1111222233334481', '2026-06-30', '789', 'credit'),
+(5, 5, '1111222233334482', '2027-05-31', '890', 'debit'),
+(6, 6, '1111222233334491', '2028-04-30', '901', 'debit'),
+(7, 7, '1111222233334501', '2029-03-31', '012', 'credit'),
+(8, 8, '1111222233334511', '2026-02-28', '111', 'debit'),
+(9, 9, '1111222233334521', '2027-01-31', '222', 'credit'),
+(9, 12, '1111222233334533', '2027-10-31', '555', 'debit'),
+(10, 10, '1111222233334531', '2028-12-31', '333', 'debit'),
+(10, 11, '1111222233334532', '2029-11-30', '444', 'credit'),
+(13, 1, '1111222233334541', '2028-12-31', '111', 'debit'),
+(13, 1, '1111222233334542', '2027-11-30', '112', 'credit'),
+(14, 2, '1111222233334551', '2029-10-31', '221', 'debit'),
+(14, 2, '1111222233334552', '2028-09-30', '222', 'credit'),
+(15, 3, '1111222233334561', '2027-08-31', '331', 'debit'),
+(15, 3, '1111222233334562', '2026-07-31', '332', 'credit');

Lecture_1/01-select.sql

@@ -0,0 +1,33 @@
+-- First lecture SELECT examples.
+-- Run 01-bankovnictvi-import.sql before executing these queries.
+
+-- This query returns all columns from the accounts table.
+SELECT * FROM accounts;
+
+-- Select only the account number and bank identifier.
+SELECT account_number, bank_id FROM accounts;
+
+-- Use WHERE to filter specific records.
+SELECT * FROM accounts WHERE currency = 'CZK';
+
+SELECT * FROM accounts WHERE balance > 1000;
+
+SELECT * FROM accounts WHERE balance < 1000 AND currency = 'CZK';
+
+SELECT * FROM accounts WHERE balance > 1000 AND currency = 'CZK';
+
+SELECT *
+FROM accounts
+WHERE (
+        currency = 'USD'
+        OR currency = 'EUR'
+    )
+    and balance < 1000;
+
+SELECT * FROM accounts WHERE currency IN ('CZK', 'USD');
+
+SELECT * FROM accounts WHERE currency NOT IN ('CZK', 'USD');
+
+SELECT * FROM clients WHERE email IS NULL;
+
+SELECT * FROM clients WHERE name LIKE 'Ja%';