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package backend
import (
"database/sql"
"fmt"
"log"
)
// newTree creates a new tree with the given width
func NewTree(database *sql.DB, width float64) {
db = database
log.Printf("Creating a new tree with a width of %f", width)
// get the current max root id
query := fmt.Sprintf("SELECT COALESCE(max(root_id), 0) FROM nodes")
var currentMaxRootID int64
err := db.QueryRow(query).Scan(¤tMaxRootID)
if err != nil {
log.Fatalf("[ E ] max root id query: %v\n\t\t\t query: %s\n", err, query)
}
// build the query creating a new node
query = fmt.Sprintf("INSERT INTO nodes (box_width, root_id, box_center, depth, isleaf, timestep) VALUES (%f, %d, '{0, 0}', 0, TRUE, %d)", width, currentMaxRootID+1, currentMaxRootID+1)
// execute the query
rows, err := db.Query(query)
defer rows.Close()
if err != nil {
log.Fatalf("[ E ] insert new node query: %v\n\t\t\t query: %s\n", err, query)
}
}
// newNode Inserts a new node into the database with the given parameters
func newNode(x float64, y float64, width float64, depth int64, timestep int64) int64 {
// build the query creating a new node
query := fmt.Sprintf("INSERT INTO nodes (box_center, box_width, depth, isleaf, timestep) VALUES ('{%f, %f}', %f, %d, TRUE, %d) RETURNING node_id", x, y, width, depth, timestep)
var nodeID int64
// execute the query
err := db.QueryRow(query).Scan(&nodeID)
if err != nil {
log.Fatalf("[ E ] newNode query: %v\n\t\t\t query: %s\n", err, query)
}
return nodeID
}
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