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The Leszynski naming convention (or LNC) is a way of naming objects in programming and database development fields. The LNC is a form of Hungarian notation which uses prefixes (called tags) to indicate the object type, control type or variable data type, and (optionally) the table field data type. Use of distinctive prefixes makes your database self-documenting; when you see frmSales in VBA code, you will know that it references a form, and when you see curSales you will know that it is a Currency variable. When selecting a query from a drop-down list, you will know that a query starting with qmak is a make-table query, while one starting with quni is a union query. This information will allow you to avoid errors such as using the SetFocus method (a control method) with a field, or trying to open a table.

The tags are always lower-case and each word of the object name is capitalized. Spaces and underscores are not used.

This naming convention is often used within the Microsoft Access community, and is standard in Visual Basic programming, but is not widely used elsewhere.

Hungarian notation (named after Charles Simonyi's native country) breaks down object names into the following elements:

[prefix(es)][tag]BaseName[Suffix/Qualifier]

The elements of the naming convention are described in the following table.

Component	Description	Example
Prefix(es)	A lowercase letter that adds extra information to the tag	p for Public variable
Tag	A three-letter sequence indicating the object type	tbl for table
BaseName	A word or two describing the object. If several words are used, each starts with a capital letter, and there are no spaces between them	OutlookContacts – contacts imported from Outlook
Suffix (RVBA), Qualifier (LNC)	A word giving more specific information about an object	ByDate – the data is sorted by date

**The Basic LNC Object Prefixes**
Object	Tag
Incomplete objects, backup objects, or objects that are under development	_ or – (In Access 2000 and later, dashes sort to the beginning of the database object list.)
Hidden system objects	zh
Displayed system objects	zs
Programmatically created temporary objects	zt
Backup copies of objects, for later copying or reuse	zz

**The Basic LNC Variable Prefixes**
Variable Type	Tag
Local variable	[no prefix]
Local static variable	s
Module-level variable	m
Public variable in a form or report module	p
Public variable declared in the Declarations section of a standard module	g

**The Basic LNC Database Object Tags**
Object	Tag
Class module	cls
Form	frm
Form (dialog)	fdlg
Form (menu)	fmnu
Form (message)	fmsg
Form (subform)	fsub
Macro	mcr
Module	bas
Query (any type)	qry
Query (append)	qapp
Query (crosstab)	qxtb
Query (data definition)	qddl
Query (delete)	qdel
Query (form filter)	qflt
Query (lookup)	qlkp
Query (make-table)	qmak
Query (select)	qry (or qsel)
Query (SQL pass-through)	qspt
Query (union)	quni
Query (update)	qupd
Report	rpt
Report (subreport)	rsub
Table	tbl
Table (attached dBASE)	tdbf
Table (attached Excel)	txls
Table (attached FoxPro)	tfox
Table (attached Lotus)	twks
Table (attached ODBC)	todb
Table (attached Paradox)	tpdx
Table (attached SQL Server)	tsql
Table (attached text)	ttxt
Table (lookup)	tlkp

**The LNC Table Field Tags**
Object	Tag
Autonumber (random non-sequential)	idn
Autonumber (replication ID)	idr
Autonumber (sequential)	ids
Binary	bin
Byte	byt
Currency	cur
Date/Time	dtm
Double	dbl
Hyperlink	hlk
Integer	int
Long	lng
Memo	mem
OLE	ole
Single	sng
Text (character)	chr
Yes/No (Boolean)	ysn

**The LNC Tags for VBA Variables**
Object	Tag
Boolean	bln
CommandBar	cbr
Control (generic; useful when cycling through controls on a form or report)	ctl
Currency	cur
Database	dbs
Double	dbl
Form	frm
Integer	int
Long	lng
QueryDef	qdf
Report	rpt
Single	sng
Snapshot	snp
String	str
Table	tbl
Type (user-defined)	typ
Variant	var

**The LNC Tags for Form and Report Controls** (may also be used in code referencing controls)
Object	Tag
Attachment	att
Bound object frame	frb
Chart (graph)	cht
Check box	chk
Combo box	cbo
Command button	cmd
Custom control	ocx
Frame	fra
Hyperlink	hlk
Image	img
Label	lbl
Line	lin
List box	lst
Option button	opt
Option group	grp
Page (on a Tab control)	pge
Page break	brk
Rectangle (shape)	shp
Subform/report	sub
Tab control	tab
Text box	txt
Toggle button	tgl
Unbound object frame	fru

**Some Typical LNC Names for Database Objects, Controls and Variables**
Object/variable name	LNC naming elements	Description
tblEmployees	tag + base name	A table of employee data
qupdSales	tag + base name	A query that updates sales data
fsubDayMax	tag + base name + qualifier	A subform that shows the maximum day
intLines	tag + base name	An Integer variable to hold a value representing the number of lines in a Word table
curSales	tag + base name	A Currency variable holding a Sales value
pstrForm	prefix + tag + base name	A public String variable holding a form name
zztblContacts	prefix + tag + base name	A backup Contacts table, for copying and filling with imported data

This article is taken from Helen Feddema's book, Expert One-on-One Microsoft Access Application Development, Wiley, ISBN 0-7645-5904-4, with some modifications.

External links

Helen Feddema 21:56, 3 August 2007 (UTC)

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