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Golang mysql

Example1

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package main

import (
"database/sql"
"fmt"
_ "github.com/go-sql-driver/mysql"
)

func main() {
db, err := sql.Open("mysql", "user:password@/database")
if err != nil {
panic(err.Error()) // Just for example purpose. You should use proper error handling instead of panic
}
defer db.Close()

// Prepare statement for inserting data
stmtIns, err := db.Prepare("INSERT INTO squareNum VALUES( ?, ? )") // ? = placeholder
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
defer stmtIns.Close() // Close the statement when we leave main() / the program terminates

// Prepare statement for reading data
stmtOut, err := db.Prepare("SELECT squareNumber FROM squarenum WHERE number = ?")
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
defer stmtOut.Close()

// Insert square numbers for 0-24 in the database
for i := 0; i < 25; i++ {
_, err = stmtIns.Exec(i, (i * i)) // Insert tuples (i, i^2)
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
}

var squareNum int // we "scan" the result in here

// Query the square-number of 13
err = stmtOut.QueryRow(13).Scan(&squareNum) // WHERE number = 13
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
fmt.Printf("The square number of 13 is: %d", squareNum)

// Query another number.. 1 maybe?
err = stmtOut.QueryRow(1).Scan(&squareNum) // WHERE number = 1
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
fmt.Printf("The square number of 1 is: %d", squareNum)
}

Example 2

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package main

import (
"database/sql"
"fmt"
_ "github.com/go-sql-driver/mysql"
)

func main() {
// Open database connection
db, err := sql.Open("mysql", "user:password@/dbname")
if err != nil {
panic(err.Error()) // Just for example purpose. You should use proper error handling instead of panic
}
defer db.Close()

// Execute the query
rows, err := db.Query("SELECT * FROM table")
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}

// Get column names
columns, err := rows.Columns()
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}

// Make a slice for the values
values := make([]sql.RawBytes, len(columns))

// rows.Scan wants '[]interface{}' as an argument, so we must copy the
// references into such a slice
// See http://code.google.com/p/go-wiki/wiki/InterfaceSlice for details
scanArgs := make([]interface{}, len(values))
for i := range values {
scanArgs[i] = &values[i]
}

// Fetch rows
for rows.Next() {
// get RawBytes from data
err = rows.Scan(scanArgs...)
if err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}

// Now do something with the data.
// Here we just print each column as a string.
var value string
for i, col := range values {
// Here we can check if the value is nil (NULL value)
if col == nil {
value = "NULL"
} else {
value = string(col)
}
fmt.Println(columns[i], ": ", value)
}
fmt.Println("-----------------------------------")
}
if err = rows.Err(); err != nil {
panic(err.Error()) // proper error handling instead of panic in your app
}
}

grinning all the time

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