gorm/postgres.go

144 lines
3.4 KiB
Go

package gorm
import (
"database/sql"
"database/sql/driver"
"fmt"
"reflect"
"time"
"github.com/lib/pq/hstore"
)
type postgres struct {
}
func (s *postgres) BinVar(i int) string {
return fmt.Sprintf("$%v", i)
}
func (s *postgres) SupportLastInsertId() bool {
return false
}
func (s *postgres) HasTop() bool {
return false
}
func (s *postgres) SqlTag(value reflect.Value, size int) string {
switch value.Kind() {
case reflect.Bool:
return "boolean"
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uintptr:
return "integer"
case reflect.Int64, reflect.Uint64:
return "bigint"
case reflect.Float32, reflect.Float64:
return "numeric"
case reflect.String:
if size > 0 && size < 65532 {
return fmt.Sprintf("varchar(%d)", size)
}
return "text"
case reflect.Struct:
if _, ok := value.Interface().(time.Time); ok {
return "timestamp with time zone"
}
case reflect.Map:
if value.Type() == hstoreType {
return "hstore"
}
default:
if _, ok := value.Interface().([]byte); ok {
return "bytea"
}
}
panic(fmt.Sprintf("invalid sql type %s (%s) for postgres", value.Type().Name(), value.Kind().String()))
}
func (s *postgres) PrimaryKeyTag(value reflect.Value, size int) string {
switch value.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uintptr:
return "serial PRIMARY KEY"
case reflect.Int64, reflect.Uint64:
return "bigserial PRIMARY KEY"
default:
panic("Invalid primary key type")
}
}
func (s *postgres) ReturningStr(tableName, key string) string {
return fmt.Sprintf("RETURNING %v.%v", s.Quote(tableName), key)
}
func (s *postgres) SelectFromDummyTable() string {
return ""
}
func (s *postgres) Quote(key string) string {
return fmt.Sprintf("\"%s\"", key)
}
func (s *postgres) HasTable(scope *Scope, tableName string) bool {
var count int
newScope := scope.New(nil)
newScope.Raw(fmt.Sprintf("SELECT count(*) FROM INFORMATION_SCHEMA.tables where table_name = %v and table_type = 'BASE TABLE'", newScope.AddToVars(tableName)))
newScope.SqlDB().QueryRow(newScope.Sql, newScope.SqlVars...).Scan(&count)
return count > 0
}
func (s *postgres) HasColumn(scope *Scope, tableName string, columnName string) bool {
var count int
newScope := scope.New(nil)
newScope.Raw(fmt.Sprintf("SELECT count(*) FROM information_schema.columns WHERE table_name = %v AND column_name = %v",
newScope.AddToVars(tableName),
newScope.AddToVars(columnName),
))
newScope.SqlDB().QueryRow(newScope.Sql, newScope.SqlVars...).Scan(&count)
return count > 0
}
func (s *postgres) RemoveIndex(scope *Scope, indexName string) {
scope.Raw(fmt.Sprintf("DROP INDEX %v", s.Quote(indexName))).Exec()
}
var hstoreType = reflect.TypeOf(Hstore{})
type Hstore map[string]*string
func (h Hstore) Value() (driver.Value, error) {
hstore := hstore.Hstore{Map: map[string]sql.NullString{}}
if len(h) == 0 {
return nil, nil
}
for key, value := range h {
hstore.Map[key] = sql.NullString{String: *value, Valid: true}
}
return hstore.Value()
}
func (h *Hstore) Scan(value interface{}) error {
hstore := hstore.Hstore{}
if err := hstore.Scan(value); err != nil {
return err
}
if len(hstore.Map) == 0 {
return nil
}
*h = Hstore{}
for k := range hstore.Map {
if hstore.Map[k].Valid {
s := hstore.Map[k].String
(*h)[k] = &s
} else {
(*h)[k] = nil
}
}
return nil
}