db2struct

README

db2struct

The db2struct package produces a usable golang struct from a given database table for use in a .go file.

By reading details from the database about the column structure, db2struct generates a go compatible struct type with the required column names, data types, and annotations.

Generated datatypes include support for nullable columns sql.NullX types or guregu null.X types and the expected basic built in go types.

Db2Struct is based/inspired by the work of ChimeraCoder's gojson package gojson

Usage

go get github.com/Shelnutt2/db2struct/cmd/db2struct
db2struct --host localhost -d test -t test_table --package myGoPackage --struct testTable -p --user testUser

Example

MySQL table named users with four columns: id (int), user_name (varchar(255)), number_of_logins (int(11),nullable), and LAST_NAME (varchar(255), nullable)

Example below uses guregu's null package, but without the option it procuded the sql.NullInt64 and so on.

db2struct --host localhost -d example.com -t users --package example --struct user -p --user exampleUser --guregu --gorm

Output:

package example

type User struct {
  ID              int   `gorm:"column:id"`
  UserName        string `gorm:"column:user_name"`
  NumberOfLogins  null.Int `gorm:"column:number_of_logins"`
  LastName        null.String `gorm:"column:LAST_NAME"`
}

Supported Databases

Currently Supported

• MariaDB
• MySQL

Planned Support

• PostgreSQL
• Oracle
• Microsoft SQL Server

MariaDB/MySQL

Structures are created by querying the INFORMATION_SCHEMA.Columns table and then formatting the types, column names, and metadata to create a usable go compatible struct type.

Supported Datatypes

Currently only a limited number of MariaDB/MySQL datatypes are supported. Initial support includes:

• tinyint (sql.NullInt64 or null.Int)
• int (sql.NullInt64 or null.Int)
• smallint (sql.NullInt64 or null.Int)
• mediumint (sql.NullInt64 or null.Int)
• bigint (sql.NullInt64 or null.Int)
• decimal (sql.NullFloat64 or null.Float)
• float (sql.NullFloat64 or null.Float)
• double (sql.NullFloat64 or null.Float)
• datetime (null.Time)
• time (null.Time)
• date (null.Time)
• timestamp (null.Time)
• var (sql.String or null.String)
• enum (sql.String or null.String)
• varchar (sql.String or null.String)
• longtext (sql.String or null.String)
• mediumtext (sql.String or null.String)
• text (sql.String or null.String)
• tinytext (sql.String or null.String)
• binary
• blob
• longblob
• mediumblob
• varbinary
• json

Documentation

Index

• Variables
• func Generate(columnTypes map[string]map[string]string, columnsSorted []string, ...) ([]byte, error)
• func GetColumnsFromMysqlTable(mariadbUser string, mariadbPassword string, mariadbHost string, ...) (*map[string]map[string]string, []string, error)
• func GetTablesFromMysqlSchema(mariadbUser string, mariadbPassword string, mariadbHost string, ...) ([]string, error)

Variables

var Debug = false

Debug level logging

Functions

func Generate

func Generate(columnTypes map[string]map[string]string, columnsSorted []string, tableName string, structName string, jsonAnnotation bool, gormAnnotation bool, dbAnnotation bool, gureguTypes bool) ([]byte, error)

Generate Given a Column map with datatypes and a name structName, attempts to generate a struct definition

func GetColumnsFromMysqlTable

func GetColumnsFromMysqlTable(mariadbUser string, mariadbPassword string, mariadbHost string, mariadbPort int, mariadbDatabase string, mariadbTable string) (*map[string]map[string]string, []string, error)

GetColumnsFromMysqlTable Select column details from information schema and return map of map

func GetTablesFromMysqlSchema

func GetTablesFromMysqlSchema(mariadbUser string, mariadbPassword string, mariadbHost string, mariadbPort int, mariadbDatabase string) ([]string, error)

GetTablesFromMysqlSchema Select table details from information schema