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QUALITY DATA: DATABASE MANAGEMENT SYSTEMS ANDQA APPLICATIONSJOEL B. SANDBERG aa 221 Forest Avenue, Emerson, New Jersey, 07630Published online: 29 May 2007.

To cite this article: JOEL B. SANDBERG (1990) QUALITY DATA: DATABASE MANAGEMENT SYSTEMS AND QA APPLICATIONS,Quality Engineering, 2:4, 473-485, DOI: 10.1080/08982119008962741

To link to this article: http://dx.doi.org/10.1080/08982119008962741

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Quality Engineering 2(4), 473-485 (1990)

QUALITY DATA: DATABASE MANAGEMENT SYSTEMS AND QA APPLICATIONS

JOEL B. SANDBERG 22 1 Forest Avenue Emerson, New Jersey 07630

Key Words

Data; Quality; Database; ata abase management system (DBMS); Flat file; Rela- tional DBMS

Database Management Systems and Quality Assurance Applications

Data. They are in every office these days. Those stacks of computer reports, sales analyses, forecasts, tests results, and surveys are everywhere. Numbers, figures, charts, graphs and paper, reams of paper. Do we have useful information or merely raw numbers?

Data are not "the end" of a journey. They are gathered as a tool to help make decisions. Data are representation, communication the who, what, where, when, and how of one time and place to another. To use data, we should understand what we have, how they were gathered, and what they represent. Then we can arrange the data in the form that helps make decisions. In computer jargon, the collection of raw data is called a database. The programs to collect, store, arrange, and report the data are called database management systems (DBMS).

This article describes :database management systems and. their use in Quality Assurance. Various types of DBMS, both manual and computerized, are described, showing the advantages and disadvantages and the growth from one type to the next. Five applications are described, showing how even simple sys-

Clopyrighr 0 1990 by Marcel Dekker. Inc.

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tems can bring together a great deal of information into quickly usable manage- ment decisions.

Manual Database Management Systems

Memory System

If you have some data, but do not want to be bogged down with systems and rules, then you can simply remember them. This seems ideal compared with the complexities of hardware and programming, but there are things to consider. First, how to transfer data between people. How much time has been wasted try- ing to get something accomplished when only one person had specific information needed? Another difficulty is organization of the data. If information is drawn from one person's memory, perspective, and analytical abilities, then the final outcome may be skewed by unintentional limitations, predisposition, or just a simple memory lapse.

Notebook

If you do not want to forget any data that you might come across, could be written in a notebook. The first piece of data would be on the first line of the first page, the next item on the next line o r page and so on. The advantages of this ''notebook data system" include: you know where to record new data; there are no restrictions on what type or form of data to record; and you always know what happened and in what order. The disadvantages of this system appear when you retrieve data. If you want to find the biggest, fastest, longest, o r how many of type X occurred, then you must read every entry and search for data required. Although there is ease of data entry in this type of sequential system, data search- ing is very difficult.

Index Cards

Keeping observations on cards offers the advantages of the notebook system and remedies some of the shortcomings. If each piece of data is recorded on a separate card, you know where to record new data, and there are no restrictions as to content o r form. However, the cards no longer show the order of the data. T o retrieve data, the cards can be arranged in order of the measurement size to find the biggest, fastest, o r longest, though this sorting is often slow and every card must be read. Again the ease and free form nature of the data collection lim- its the usefulness of the data retrieval for analysis.

Forms

Forms start to bring real order to data collection. A preprinted form always gathers the same information and in the same manner. You can physically sort

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DBMS AND QA 475

forms to find the biggest, fastest, o r how many of one type, but you can still organize the forms by only one item type at a time. The uniformity of data col- lected might be a limitation if something special occurs and there is no place to write it.

Filing Cabinets

Filing cabinets can be thought of as a collection of folders with forms. Where a single form collects one type of information, a filing cabinet collects several forms with different information. For example, the number of dependents is on your employment application, therefore you do not write it on your weekly time sheet for accounting to figure the withholding taxes. A purchasing agent writes the quantity purchased of each item on the purchase order form. But the part description, vendor name and address, unit of measure, manufacturer's name, and part number can be shortened to a vendor number and part number. The rest of the information comes from the vendor master files and the part master files. Combining the information from several forms increases the amount of informa- tion available and decreases the amount of information required on each separate form.

Computerized Database Management Systems

Computer data systems offer many different approaches to the problems of col- lecting, storing, retrieving, arranging, and presenting data. Many computer pro- grams parallel the systems described above. The choice of a program and equip- ment is a matter of understanding your needs and how much effort, and money, you are willing to spend, then matching them up with various program's capabilities.

Computerized Memory System

While computers have a great deal of memory, a computer system to remember information with no order is not an improvement over the manual method. Since computers store information as a series of similar looking numbers, a program needs to have a set of rules and patterns for placing the data into memory.

Computerized Notebook

Computerized "notebook" systems for data collection do exist and are called "text-based management systems" (1). These programs offer ease of use and few restrictions on data format. But the flexibility limits the usefulness to simple

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applications. For example, a computer program cannot determine the number of rubber bands shipped in a month unless it knows that the number of rubber bands for each day is always stored in the same place in the daily records. Since note- . book systems have few restrictions on the organization of data, only limited searches become reasonable.

Computerized Index Cards and Forms

Computer programs that do the same things as index cards or forms-based data systems are both implemented using a method that is called a flat file. A flat file can be visualized as a large accounting sheet with rows and columns across the page. Columns, also called fields, run vertically up and down the "page" and each has a title for the particular type of data collected (i.e., last name; first name; telephone number; age, etc.). The rows, or records, run horizontally across the "page." Each record fills in every column with information (data) for one particular set of conditions (e.g., Smith, Mary, 555-1234, 32). The combina- tion of fields and records is a table. The same type of information is always in the same column for every record in a table, allowing the computer to know how to store or retrieve specific information. Although flat files are organized inside the computer as rows and columns, they do not necessarily look that way to the user. Programs arrange the information on the screen or printer in ariy way the user describes, often to match the existing paper forms. The advantages of using a flat file DBMS are simplicity and ease of getting started. You input the pieces of information on the screen as you go. Information can be entered immediately. Any completed record can be displayed by typing just part of one field.

Computenied Filing Cabinet

The most popular type of personal computer database management system pro- grams use the multiple form, filing cabinet type of system. These are relational database systems. Today's relational database management system computer pro- grams include all the flexibility of the flat file programs described above plus the ability to deal with many different tables and relationships between tables. There are more than 50 implementations of relational database technology currently available (2,3).

Two types of relational DBMS programs are available, those with and those without an integrated programming language. DBMSs without an .integrated pro- gramming language work much like word processing or spreadsheet programs. They have a fixed set of commands and operations. These commands are accessed through "on screen" instructions, called prompt by example or query by example. The instruction code is optimized for fast operation and to reduce the possibilities of corrupting the data by operator error. But since the instructions available are fixed, only those types of operations and analyses built into the pro-

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DIIMS AND QA 477

gram can be accomplished. Fixed command systems tend to be easier to learn and quicker to initiate use than programs that include a programming language. '

DBMSs that include a complete programming language allow use of both the power of special database commands and the flexibility of writing your own pro- grams in a language like BASIC or Pascal. Previously complicated tasks like sort- ing and searching through files are added to your programs with a single com- mand. The database portion of the system does the hard work of organizing and keeping track of the data. The programs you write are special to your situation and may never be found in mass-marketed software. These products also include prompt by example, allowing you to easily use the built-in database commands without writing your own program if you choose. If you are converting a manual system to a computer, a separate table would be developed for each form used manually. Then relationships are defined to explain how to take data from several tables for special analysis.

Quality Assurance Applications of Database Computer Programs

Several examples of personal computer database applications are described to show the simplicity and power that can be obtained with a small amount of effort and investment. Some of the applications use only a single table. Others use many tables tied together in elaborate ways.

Returned Material Tracking

A simple, one table, database was developed to track and record returns from customers. The table has 23 fields or columns per record. The data entry screen (,Fig. 1) also serves as the data editing screen. Only seven or eight of the 23 items

R e t u r n e d M a t e r i a l A u t h o r i z a t i o n - Data E n t r y S c r e e n

R M A /I: Cus tomer :

P a r t P r o b l e m : Q u a n t i t y :

D a t e Opened: J o b I I :

D e p a r t m e n t :

D a t e M a t e r i a l R e c e i v e d Back : C u s t o m e r ' s S h i p p i n g N o t i c e 1: E v a l u a t o r : Done :

D i s p o s i t i o n ( C o d e ) : D e f e c t Code : Q u a n t i t y Bad : C r e d i t $ : Memo B : D a t e :

R e p l a c e m e n t O r d e r d : S h o r t Form I/ :

F o l l o w Up Date :

S c h e d u l e d S h i p D a t e : A c t u a l S h i p D a t e :

Figure I . Returned Malerial Aurhorization-data entry screen

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478 . SANDBERG

are known when a customer calls and asks to return defective products. The Returned Material Authorization (RMA) coordinator enters as much data as is available while on the phone with the customer, and later edits the record to add more information as it becomes known.

From this one table six reports are issued each week. Figure 2 shows the lssued RMAs report. This report shows every RMA issued during the week, sorted by department, with the information requested by division management. Additional reports list other fields from the database of particular interest to specific groups. The general manager watches the number of RMAs issued and the total dollar credit exposure. The production manager looks at the promised replacement ship dates. The controller reads the credited RMA report as a cross check on his accounting records. The engineering manager checks the open

Re tu rned M a t e r i a l A u t h o r i z a t i o n .*ISSUED*' R M A s For P e r i o d S t a r t i n g 09/01/87 - Ending 09/15/87

. P a g e : 1 Da te : 01/10/90

I s s u e d R H A l J o b I Customer , Problem Q ~ Y VaJue

Depar tmen t : 01 09/15/87 2991 4051176 EMax SCRATCHES 12 $83.64 09/15/87 3036 4050903 EMax DID NOT MEET M I N I M U N LOT 58 $469.80

SIZE 09/08/87 3053 4051056 P o o l e Wrong T h i c k n e s s m a t e r i a l 117 $819.00

s h i p p e d 09/09/87 3054 4050313 P e n t i o n C h i p s , W a r p e d , C r a c k i n g , 3203 9 , 2 2 4 . 6 4

B r e a k i n g 09/15/87 3055 4050902 DataByte SHINNY SPOTS A N D NO TICK 1051 1 ,839 .25

H A R K 09/15/87 3056 4050891 M l l l e t t H O L E S T O O CLOSE TOGETHER 450 4.846.50

( H A Y H A V E USED WRONG PUNCHING D I E )

Number o f RMAs 6 Depar tment T o t a l S17,282.83

Depar tmen t : 04 09/08/87 3048 7079573 Mat r ix

09/15/87 3057 7078645 High land 09/15/87 3058 7078902 Highland 09 /15 /87 3059 7078933 High land 09 /15 /87 3060 7079329 Highland 09/15/87 3061 7079329 Highland

Number o f ?MAS 6

RESISTIVITY SHOULD H A V E 150 $0.00 C A L L E D F O R AS DEPOSITED VISUAL 32 $152.00 VISUAL 4 $125.60 14 VISUAL 17 $566.72 30 VISUAL 57 1 , 1 1 0 . 0 0 17 VISUAL 105 $688. 16

Depar tment T o t a l $2 ,642 .48

Depar tmen t : 07 09/08/87 3049 7078581 Van Len te B r i d g i n g , b l i s t e r s ,

s c r a t c h e s , l i n e w i d t h 09/08/87 3050 7079561 Van Len te V o i d s . b r i d g i n g . l i n e w i d t h . 31 $806.00

b l i s t e r s , c h i p - 09/08/87 3051 7078680 West ighou B r i d g i n g , b l i s t e r s , v iod 27 $702.00 . 09/08/87 3052 7079564 Van L e n t e S p a c i n g , b l i s t e r s , s c r a t c h e s 55 1 , 4 3 0 . 0 0 09/08/87 3100 7079563 Van Len te B r i d g i n g , s c r a t c h e s , l i n e 59 1 , 5 3 4 . 0 0

w i d t h Number o f R M A s 5 Depar tment T o t a l $5 ,148 .00

Number or R M A s 17 D i v i s i o n T o t a l $25 ,073 .31

Figure 2. Issued Returned Material Authorization Division Report.

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DBMS AND QA 479

evaluations report to be sure the engineers are supporting customer problems promptly. And the quality assurance manager makes sure that each replacement is followed with a call to assure the problem is truly resolved. Other ad hoc reports are generated, using the query by example section of the database language, without writing special programs.

Prior to using a computerized database system, returns were tracked using a notebook-with each return taking the next line in the book. The computer pro- gram provided more information and analysis in ten minutes than the manual sys- tem could provide in four hours a week.

CIDEP Data Sorting-Another Flat File

GIDEP (the Government-Industry Data Exchange Program) (4) generates hun- dreds of reports each year to help prevent recurrence of previously documented failures in military components, assemblies, and contracts. A personal computer database application was used to sort through the reports to identify the few per- tinent to each day's activity.

An engineer reviewed every purchase order to verify that components identified as defective in GIDEP reports were not being used. Searching through file drawers .of reports for every item ordered was not only time consuming, it was subject to error and oversight. But the failure to screen materials against prior warnings causes major customer concerns.

The GIDEP failure experience reports were summarized into a database. A set of summary lists were generated, each listing the report number, date, manufac- turer identified, and part number listed in the report. When an engineer reviewed a purchase order for a particular item, it was only necessary to glance at the sum- mary and check if the item being ordered appeared on the list. In the few cases where there was a match, he would retrieve and review the full GIDEP report and check the details for applicability. Using a computerized database makes available more data to make decisions that otherwise would remain in filing cabinets.

Laboratory Data Management

A metal refining operation was required to perform several different assays on each batch before shipping. The number and types of tests required were different for each type and grade of metal produced. Keeping track of each batch and which tests had been conducted, and collecting all results required the labor of two clerks, Tracking long-term trends was a manual operation and therefore sel- dom done.

A multitable database was structured on a local area network to automate the data collection process. One table listed all product types and the tests required.

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Another logged each batch and recorded which tests had been completed. A separate table was customized for each type of test to record the data as meas- u red.

When all required tests were completed, a summary data sheet was prepared and sent to the customer. Since the data were in the database, trends could be spotted quickly. The program could sort for results concerning any particular pro- duct.

Nonconforming Material Reporting: A Multitable Database

Most organizations record their nonconforming material in some manner. A system for ,controlling nonconforming materials is required of contractors and manufacturers by the Department of Defense, National Aeronautics and Space Administration (NASA), the federal Food and Drug Administration's Good Manufacturing Practices (GMP), the Nuclear Regulatory Commission (NRC), and most other quality systems. Inspection departments soon have drawers filled with notices showing what parts failed, the vendor, and if the item was used, repaired, returned, or scrapped. Yet few organizations review data to identify which problems are truly significant and require attention.

A database system was implemented to collect data directly from the form already used. The system tracked internal departments as well as external ven- dors. Nine tables with 80 fields were used to prepare eight reports. The tables drew information from one another automatically.

Figure 3 shows a list of nonconformances for one supplier. Each supplier was sent this type of report, listing nonconformances identified in items he had sup- plied, to discuss problems perceived, and corrective action. A six-month Pareto analysis by failure type tracked changes for one vendor. This is shown in Figure 4a in tabular form, Figure 4b as a stacked bar chart of failure types, and in Fig- ure 4c as the cumulative percent defective by failure type. All were available by selecting the appropriate choices from the computer screen menus. The "worst vendor" report was sorted four ways: total part cost, number of defective com- ponents, number of reports, and number of defective characteristics. Similar reports were run for worst part and worst failure cause. Figure 5 shows one of these reports. Note that the failure type with the largest number of defective parts is not the one with the highest dollar impact.

Hundreds of sheets of information were going unread before this system was installed. No analysis of the data was possible. Now high failure rate parts, fault types, and vendors are quickly identified and targeted for investigations and corrective action.

Ceramic Products Process Quality: A Relational Database

A ceramic products operation consisted of five major operations; mixing, cast- ing, punching, firing, and fabrication. A single batch of products would take 7-10

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N o n - C a n f ~ r m l n g M a t e r l a l R e p o r t

O l l l O l O O 2 0 : 4 0 : 5 4

V e n d o r : E l a c t r o Y E S

R ~ L I t P m r r Num.

Num am - - - - - - - - - - - - - - - - - - - 11135 1 37117111792-U

F r o m : 0 i l l 5 l B 9 T h r o u g h : 05114189

R D a r c r l p t l n n PDIYO I R s s ' d R e J D a t e O i

e P ry c t 0 P - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - - - - - - - - - - - - - - - - - - - - - - - - - - - - J PCB ASSY. MICROPROCESSOR 7 0 3 0 2 2 I 1 0 4 l 1 0 1 B U 9

C PCB AOSY, LPS

C PCB ASSY. LPS

C PCB ASSY. LAMP P I S

A PCB ASSY, DISPLAY

A PCB AS6Y. DISPLAY

B PCB ABSY. CPU L 6E

B PCB ASSY. TIMER REFERENCE

1 SIONAL ELECTRONICS

I SIQNAL ELECTRONICS

- RESISTOR. PREC. 3.00K. 0 .1X

- WIRE. STR. 22QA. EIOOV. BLACK

- HARNESS. CONTRAST CONTROL

H PCB ASSY. INDEXER

A PCB ASSY. DISPLAY .

B PCB ASSY. POWER SUPPLY 7 8 3 0 5 0 I I OSI1010B 22

C PCB I\SSY. INTERFACE 10005 1 5 0 5 / 1 2 / 0 9 11

C PCB ASSY. INTERFACE 1 0 0 0 5 8 1 0 5 1 1 2 1 8 9 11

D PCB ASSY. INTERFACE

0 PCB ASSY. INTERFACE

D PCB ABSY. INTERFACE

0 PCB ASSY.. INTERFACE 100022 25 25 0 5 1 1 2 1 0 8 11

D PCB AB6Y. INTERFACE 100022 25 25 0 5 1 1 2 1 8 9 11

P a g e 1

Cnmmenta

------------------------------.-------- DAMAGED COMPONENT K I - K 4 CRACKED PLASTIC

COVER

INSTALLEO WROW - F I N I(4 BACKWARD

9 2 YRONQ COMPONENT

WIRINOISOLOERINO U2 NOT SOLDERED

DS I 0 NOT I N L I N E WlTH OS19-DS18

INSTALLED WRONO - Uq P I N BENT

PART M lSSINO - C8 OMITTED

INSTALLEO WRONO - U2 REVEISED POLARITY

C 2 . C I 4 . C I B - 2 0 WRONB VOLTADE

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WRDNO PaRT - WIRE 2 2 QA 8OOV. BLACK

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INSTALLED WROM - C3 REVERSED PULARITY

WIRINQISOLOERINO SOLDER DRIDOE EXCESS

SOLDER

PART MISSINO - F N 72 OMITTED

PART MISSINQ - JUMPER NOT INSTALLEO

PART MISSING - C44 .95 .48 .51 .59

INSTALLATION OMITTED

PART MISSINO - 2 P I N NOT 1NSTALLEO

C - 1 0 INSTALLED IMPROPERLY

INSTALLEO WROND - PERMANENT LOCATION

FOR C 8 Q C C70

PART MISSINO - RN 8 . RN 7. RN 8

INSTALLATION OMITTED

BOARD 1 7 0 0 - 0 2 8 7 REV B I S REV AOMITTEO

T o t a l N u m b e r O r R e p o r t s : I 5 T o t a l Number OF D l r c r s p s n c l e a : 23

Figure 3. NCMR Vendor Report.

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Nonconforming M a t e r i a l Repo r t - V e n d o r - F a i l u r e Code H i s t o r y O l / l O / g O 2 0 : 2 6 : 2 6

Vendor : E lec t roYES F o r : 11 /19 /88 To: 05/19/89

Number O f Nonconformances F o r Each F a i l u r e Code I n Each P e r i o d

B e g i n -------- 05 /06 /89 0 4 / 2 2 / 8 9 0 4 / 0 e / 8 9 0 3 / 2 5 / 8 9 03 /11 /89 02/25/89 0 2 / 1 1 / 8 9 0 1 /28 /89 0 1 / 1 4 / 8 9 1 2 / 3 1 /88 12 /17 /88 12 /03 /88 11/19/88

E n d i n g -------- 05 /19 /89 05 /05 /89 0 4 / 2 1 / 8 9 0 4 / 0 7 / 8 9 0 3 / 2 4 / 8 9 0 3 / 10/89 0 2 / 2 4 / 8 9 0 2 / 10/89 0 1 / 2 7 / 8 9 01 /13 /89 12 /30 /88 12 /16 /88 12 /02 /88

F a i l u r e Codes 201 2 0 2 203 204 210 9 7 1 4 4 0 900 999 200 O t h e r T o t a l --- --- --- --- --- --- --- --- --- --- ----- -----

6 8 4 0 1 1 0 2 1 0 2 25 ~ 1 0 1 0 0 0 0 ~ 0 0 1 0 3

2 3 6 3 1 0 0 1 0 0 0 16 1 4 2 5 6 0 0 0 0 0 1 19 5 4 6 3 0 0 0 0 0 0 0 18

1 0 4 6 1 4 4 2 3 2 3 0 3 51 1 1 6 7 3 1 0 0 0 1 0 3 32 4 5 4 0 2 1 0 0 0 2 0 18

3 9 1 7 7 2 4 1 2 0 0 1 2 75 2 3 6 2 5 5 3 0 0 0 4 30 2 2 0 0 0 0 0 0 0 0 0 4 6 9 2 0 1 2 0 0 0 0 1 2 1 8 3 8 0 4 3 0 1 0 0 2 29

F a i l u r e Code -------

20 1 202 203 204 210 91 1 4 40 900 999 200

D e s c r i p t i o n ......................... PART MISSING W R O N G PART I N S T A L L E D W R O N G D A M A G E D COMPONENT W I R I N G O R S O L D E R I N G WRONG R E V I S I O N D I R T Y MISC. M I S C E L L A N E O U S N O NONCONFORMANCE ASSEMBLY MISC.

,Figure #a. Nonconforming Material Report-Vendor Pareto Analysis.

days for all five steps, depending on the product type. Each group reported daily yields to management and each tried to recognize and correct problems in their area. Efforts to identify the effects of one group's output on others were compli- cated by the various processing times for the different products and the reporting by dates.

A database was established to correlate results by product type and batch numbers instead of dates. Five tables were established to collect data, by batch number, from each group. Other tables contained standard formulations, process parameters, and other background information. Forty process controlling inputs and forty resulting measurements were recorded for each batch.

This program built relationships, based on batch numbers, among the informa- tion in various tables. The total line yields were calculated based on specific pro- cess values, rather than averaged over a week or month. Problems were identified as being due to specific causes such as a bad raw chemical lot or short mixing time. Troubleshooting became more scientific and less intuitive. Dates no longer

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DBMS AND QA

Vendor F a ~ l u r e History ElectroYES

Number of Disc repanc 1 es 80 r

Figure 46. Vendor failure history by week graph.

Vendor Fa l l u re Causes EleciroYes

100

75

50

25 -Cumulative Percen t

=Number of

0 DISC.

Fa 1 1 ure Codes

Figure 4c. Vendor failure causes by type graph.

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Nonconfor ing M a t e r i a l s Repor t s - T a l l y . O f F a i l u r e Codes

For : 04 /01 /89 To: 05 /01 /89 01 /10 /90 20:38:46

F C F a i l u r e Code T o t a l T o t a l T o t a l T o t a l 11 Narne/Descr ip t ion 8 R e p o r t s L i n e s I t e m s

PART MISSING 303 PART NOT FUNCTIONAL 430 SCRATCHED MISC. 210 WIRING OR SOLDERING 302 ASSY. NOT FUNCTIONAL 954 D A M A G E D IN HOUSE 203 INSTALLED W R O N G 202 WRONG PART 140 THREADS MISC. 312 EXCESSIVE NOISE 900 MISCELLANEOUS

Figure 5. Nonconforming Materials Reports-most frequent failure types.

were important or shown, since batch numbers and process parameters now con- trolled the organization of the data.

DBMS = Understanding = Improvements = Savings = Profits

Databases are used in many parts of today's information-rich society. Inventory systems, bank accounts, airline flight schedules, tax records, medical histories, and laboratory test results are all stored using computer database management systems. If you are recording the same type of information more than a handful of times, a DBMS is probably the best way to store and retrieve the information.

Quality assurance organizations often have an abundance of inspection results, test measurements and audit observations. Utilizing a computer and DBMS pro- gram can organize and use the data to help all departments understand the interre- lationships between operations. Incidents that might have taken hours o r days to look up manually are readily retrievable. Analyses that were done only once a year can now be calculated weekly or daily.

Since data are all around us, DBMSs should be used to take control of the data instead of being inundated by them. Programs, from text-based systems to flat files and relational multitable systems are available and can quickly be adapted to use the data and not merely file them. Data that exist represent a history of what has happened. Failure to use the data available may be ignoring the most power- ful and lowest cost asset available to any organization. The development and use of database management systems will lead to increased awareness and understanding of what has happened, what is happening now, and will result in the ability to control what will happen in the future.

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URMS AND QA

References

1. TBMS: Database Power Unleashed. PC Magazine (November 15, 1986). 2. The concept of a relational system of data representation was first developed by Dr. E. Codd,

of IBM, in August 1979. His work established the requirements for systems to meet Dr. Codd's definition of a relational database system. None of the commercial computer programs currently available meet all of the requirements set by Dr. Codd. In this article, a relational database system will be whatever each program publisher claims it to be, without regard to the original definitions.

3. Project Database 3. PC Magazine (April 12, 26, and May 17, 1988). 4. Government-Industry Data Exchange Program, GIDEP Operations Center, Naval Weapons Sta-

tion, Seal Beach, Corona, CA 91720. 5. MIL-STD-1556B. Government-Industry Data Exchange Program, Naval Pub!ications and

Forms Center, Philadelphia, PA.

About the Author: Joel B. Sandberg is a Certified Quality Engineer and a Certified Reliability Engineer of the ASQC. He has earned a M.S. from Fairleigh-Dickinson University and a B.S. in Electrical Engineering from Northeastern University. He has fifteen years experience as a quality, reliability, and manufacturing engineer in the military electronics, semiconductor equipment, and biochemical instrumentation fields.

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