func main() {
db := dbf.New()
if err := db.Create(Note{}); err != nil {
panic(err)
}
db.Append(Note{"Tom", 444})
db.Append(Note{"Bob", 555})
db.Append(Note{"Stan", 777})
err := db.SaveFile("temp.dbf")
if err != nil {
panic(err)
}
db, err = dbf.LoadFile("temp.dbf")
if err != nil {
panic(err)
}
iter1 := db.NewIterator()
for iter1.Next() {
n := new(Note)
iter1.Read(n)
n.Amount = 12
iter1.Write(n)
fmt.Println(*n)
}
iter := db.NewIterator()
for iter.Next() {
n := new(Note)
iter.Read(n)
fmt.Println(*n)
}
err = db.SaveFile("temp.dbf")
if err != nil {
panic(err)
}
}
func save(csvfile, dbffile, equals string) {
fl, err := os.Open(csvfile)
if err != nil {
log.Fatal(err)
}
defer fl.Close()
r := csv.NewReader(fl)
// we assume that first row contains field names
records, err := r.ReadAll()
if err != nil {
log.Fatal(err)
}
// analyze data types
uniq := map[string]bool{}
isBool := map[string]bool{"T": true, "t": true, "F": true, "f": true, "y": true, "Y": true, "N": true, "n": true}
names := []FieldName{}
truncCount := 0
// inference
for row, rec := range records {
for j, field := range rec {
if row == 0 {
if len(field) > 10 {
log.Fatal("Field name can not be over 10 characters long ", field)
}
if uniq[field] {
log.Fatal("Field names must be unique ", field)
}
uniq[field] = true
names = append(names, FieldName{name: field, typ: None, length: 1})
continue
}
if names[j].typ != Alpha {
// analyze types
if names[j].typ != Float {
if _, err := strconv.ParseInt(field, 0, 64); err == nil {
names[j].typ = Int
continue
}
}
if _, err := strconv.ParseFloat(field, 64); err == nil {
names[j].typ = Float
continue
}
if isBool[field] {
names[j].typ = Bool
continue
}
// at this point - must be Alpha
names[j].typ = Alpha
}
if len(field) > 254 {
truncCount++
}
if len(field) > 254 && !names[j].truncate {
log.Println("Field is longer than 254 characters, and will be truncated '", names[j].name, "'")
names[j].truncate = true
records[row][j] = records[row][j][:250] + "..."
}
if names[j].length < len(field) {
names[j].length = len(field)
if len(field) > 254 {
names[j].length = 254
}
}
}
}
if truncCount > 0 {
log.Println("Number of truncated fields:", truncCount, "\n")
}
db := dbf.New()
log.Println("Creating table:")
log.Println("------------------------")
for _, f := range names {
switch f.typ {
case None, Alpha:
db.AddTextField(f.name, uint8(f.length))
log.Println("Text field:", f.name, "size:", f.length)
case Bool:
db.AddBoolField(f.name)
log.Println("Bool field:", f.name)
case Int:
db.AddIntField(f.name)
log.Println("Int field:", f.name)
case Float:
db.AddFloatField(f.name)
log.Println("Float field:", f.name)
}
}
log.Println("------------------------")
equalsFNum, equalsVal, filterCount := -1, "", 0
if equals != "" {
arr := strings.Split(equals, "=")
equalsFNum, err = strconv.Atoi(arr[0])
if err != nil {
log.Fatal("filter should be a field number, instead it is ", arr[0])
}
equalsVal = arr[1]
}
count := 0
for row, rec := range records {
if row == 0 {
continue
}
if equalsFNum != -1 {
if equalsFNum > len(rec)-1 {
log.Fatal("filter field number outside of record length bounds: ", equalsFNum)
}
if rec[equalsFNum] != equalsVal {
filterCount++
continue
}
}
n := db.AddRecord()
count++
for j, field := range rec {
db.SetFieldValue(n, j, field)
}
}
log.Println("Filtered records:", filterCount)
log.Println("Total records loaded:", count)
if err := db.SaveFile(dbffile); err != nil {
log.Fatal(err)
}
}