gosora/query_gen/lib/querygen.go

/* WIP Under Construction */
package qgen

import "errors"

var DB_Registry []DB_Adapter
var No_Adapter = errors.New("This adapter doesn't exist")

type DB_Table_Column struct
{
	Name string
	Type string
	Size int
	Null bool
	Auto_Increment bool
	Default string
}

type DB_Table_Key struct
{
	Columns string
	Type string
}

type DB_Select struct
{
	Table string
	Columns string
	Where string
	Orderby string
	Limit string
}

type DB_Join struct
{
	Table1 string
	Table2 string
	Columns string
	Joiners string
	Where string
	Orderby string
	Limit string
}

type DB_Insert struct
{
	Table string
	Columns string
	Fields string
}

type DB_Column struct
{
	Table string
	Left string // Could be a function or a column, so I'm naming this Left
	Alias string // aka AS Blah, if it's present
	Type string // function or column
}

type DB_Field struct
{
	Name string
	Type string
}

type DB_Where struct
{
	Expr []DB_Token // Simple expressions, the innards of functions are opaque for now.
}

type DB_Joiner struct
{
	LeftTable string
	LeftColumn string
	RightTable string
	RightColumn string
	Operator string
}

type DB_Order struct
{
	Column string
	Order string
}

type DB_Token struct {
	Contents string
	Type string // function, operator, column, number, string, substitute
}

type DB_Setter struct {
	Column string
	Expr []DB_Token // Simple expressions, the innards of functions are opaque for now.
}

type DB_Limit struct {
	Offset string // ? or int
	MaxCount string // ? or int
}

type DB_Stmt struct
{
	Contents string
	Type string // create-table, insert, update, delete
}

type DB_Adapter interface {
	GetName() string
	CreateTable(name string, table string, charset string, collation string, columns []DB_Table_Column, keys []DB_Table_Key) (string, error)
	SimpleInsert(name string, table string, columns string, fields string) (string, error)
	SimpleReplace(name string, table string, columns string, fields string) (string, error)
	SimpleUpdate(name string, table string, set string, where string) (string, error)
	SimpleDelete(name string, table string, where string) (string, error)
	Purge(name string, table string) (string, error)
	SimpleSelect(name string, table string, columns string, where string, orderby string, limit string) (string, error)
	SimpleLeftJoin(name string, table1 string, table2 string, columns string, joiners string, where string, orderby string, limit string) (string, error)
	SimpleInnerJoin(string,string,string,string,string,string,string,string) (string, error)
	SimpleInsertSelect(string,DB_Insert,DB_Select) (string,error)
	SimpleInsertLeftJoin(string,DB_Insert,DB_Join) (string,error)
	SimpleInsertInnerJoin(string,DB_Insert,DB_Join) (string,error)
	SimpleCount(string,string,string,string) (string, error)
	Write() error
	
	// TO-DO: Add a simple query builder
}

func GetAdapter(name string) (adap DB_Adapter, err error) {
	for _, adapter := range DB_Registry {
		if adapter.GetName() == name {
			return adapter, nil
		}
	}
	return adap, No_Adapter
}