63 lines
1.7 KiB
V
63 lines
1.7 KiB
V
module main
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import pg
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struct Customer {
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id int
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name string
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nr_orders int
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country string
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}
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fn main() {
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db := pg.connect(pg.Config{
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host: 'localhost' //'127.0.0.1'
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user: 'postgres'
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dbname: 'customerdb'
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}) or {
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println('failed to connect')
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println(err)
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return
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}
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nr_customers := db.select count from Customer
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println('Total customers: $nr_customers')
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// V syntax can be used to build queries
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println('----------------------------------------------------------------')
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bg_country := 'Bulgaria'
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bg_customers := db.select from Customer where country == bg_country && id != 2
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for customer in bg_customers {
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println('$customer.country | $customer.id - $customer.name')
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}
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println('----------------------------------------------------------------')
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ru_customers := db.select from Customer where country == 'Russia'
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for customer in ru_customers {
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println('$customer.country | $customer.id - $customer.name')
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}
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// by adding `limit 1` we tell V that there will be only one object
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println('----------------------------------------------------------------')
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existing := db.select from Customer where id == 1 limit 1 or { panic(err) }
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println('Existing customer name: $existing.name')
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println('Existing customer full information:')
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println(existing)
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println('------------------------------------------------------------------------')
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q := Customer{}
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// It's easy to handle queries that don't return any data
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if anon := db.select from Customer where id == 12345 && name == q.name &&
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nr_orders > q.nr_orders limit 1 {
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println('Non existing customer name: $anon.name')
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}
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// Insert a new customer
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nc := Customer{
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name: 'John Doe'
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nr_orders: 10
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}
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db.insert(nc)
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}
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