litedb

Documentation

Index

• Variables
• func IsByteArrayOrSlice(value reflect.Value) bool
• func RegisterDialect(name string, dialect Dialect)
• type DefaultForeignKeyNamer
  • func (DefaultForeignKeyNamer) BuildKeyName(kind, tableName string, fields ...string) string
• type Dialect
  • func GetDialect(name string) (dialect Dialect, ok bool)
• type SQLCommon

Variables

var ParseFieldStructForDialect = func(field *StructField, dialect Dialect) (fieldValue reflect.Value, sqlType string, size int, additionalType string) {
	// Get redirected field type
	var (
		reflectType = field.Struct.Type
		dataType, _ = field.TagSettingsGet("TYPE")
	)

	for reflectType.Kind() == reflect.Ptr {
		reflectType = reflectType.Elem()
	}

	fieldValue = reflect.Indirect(reflect.New(reflectType))

	if gormDataType, ok := fieldValue.Interface().(interface {
		GormDataType(Dialect) string
	}); ok {
		dataType = gormDataType.GormDataType(dialect)
	}

	if dataType == "" {
		var getScannerValue func(reflect.Value)
		getScannerValue = func(value reflect.Value) {
			fieldValue = value
			if _, isScanner := reflect.New(fieldValue.Type()).Interface().(sql.Scanner); isScanner && fieldValue.Kind() == reflect.Struct {
				getScannerValue(fieldValue.Field(0))
			}
		}
		getScannerValue(fieldValue)
	}

	if num, ok := field.TagSettingsGet("SIZE"); ok {
		size, _ = strconv.Atoi(num)
	} else {
		size = 255
	}

	notNull, _ := field.TagSettingsGet("NOT NULL")
	unique, _ := field.TagSettingsGet("UNIQUE")
	additionalType = notNull + " " + unique
	if value, ok := field.TagSettingsGet("DEFAULT"); ok {
		additionalType = additionalType + " DEFAULT " + value
	}

	if value, ok := field.TagSettingsGet("COMMENT"); ok {
		additionalType = additionalType + " COMMENT " + value
	}

	return fieldValue, dataType, size, strings.TrimSpace(additionalType)
}

ParseFieldStructForDialect get field's sql data type

Functions

func IsByteArrayOrSlice

func IsByteArrayOrSlice(value reflect.Value) bool

IsByteArrayOrSlice returns true of the reflected value is an array or slice

func RegisterDialect

func RegisterDialect(name string, dialect Dialect)

RegisterDialect register new dialect

Types

type DefaultForeignKeyNamer

type DefaultForeignKeyNamer struct {
}

DefaultForeignKeyNamer contains the default foreign key name generator method

func (DefaultForeignKeyNamer) BuildKeyName

func (DefaultForeignKeyNamer) BuildKeyName(kind, tableName string, fields ...string) string

BuildKeyName returns a valid key name (foreign key, index key) for the given table, field and reference

type Dialect

type Dialect interface {
	// GetName get dialect's name
	GetName() string

	// SetDB set db for dialect
	SetDB(db SQLCommon)

	// BindVar return the placeholder for actual values in SQL statements, in many dbs it is "?", Postgres using $1
	BindVar(i int) string
	// Quote quotes field name to avoid SQL parsing exceptions by using a reserved word as a field name
	Quote(key string) string
	// DataTypeOf return data's sql type
	DataTypeOf(field *StructField) string

	// HasIndex check has index or not
	HasIndex(tableName string, indexName string) bool
	// HasForeignKey check has foreign key or not
	HasForeignKey(tableName string, foreignKeyName string) bool
	// RemoveIndex remove index
	RemoveIndex(tableName string, indexName string) error
	// HasTable check has table or not
	HasTable(tableName string) bool
	// HasColumn check has column or not
	HasColumn(tableName string, columnName string) bool
	// ModifyColumn modify column's type
	ModifyColumn(tableName string, columnName string, typ string) error

	// LimitAndOffsetSQL return generated SQL with Limit and Offset, as mssql has special case
	LimitAndOffsetSQL(limit, offset interface{}) string
	// SelectFromDummyTable return select values, for most dbs, `SELECT values` just works, mysql needs `SELECT value FROM DUAL`
	SelectFromDummyTable() string
	// LastInsertIdReturningSuffix most dbs support LastInsertId, but postgres needs to use `RETURNING`
	LastInsertIDReturningSuffix(tableName, columnName string) string
	// DefaultValueStr
	DefaultValueStr() string

	// BuildKeyName returns a valid key name (foreign key, index key) for the given table, field and reference
	BuildKeyName(kind, tableName string, fields ...string) string

	// NormalizeIndexAndColumn returns valid index name and column name depending on each dialect
	NormalizeIndexAndColumn(indexName, columnName string) (string, string)

	// CurrentDatabase return current database name
	CurrentDatabase() string
}

Dialect interface contains behaviors that differ across SQL database

func GetDialect

func GetDialect(name string) (dialect Dialect, ok bool)

GetDialect gets the dialect for the specified dialect name

type SQLCommon

type SQLCommon interface {
	Exec(query string, args ...interface{}) (sql.Result, error)
	Prepare(query string) (*sql.Stmt, error)
	Query(query string, args ...interface{}) (*sql.Rows, error)
	QueryRow(query string, args ...interface{}) *sql.Row
}

SQLCommon is the minimal database connection functionality gorm requires. Implemented by *sql.DB.