AU612263B2 - Method of data retrieval from a data base and a system therefor - Google Patents

Description

js~ 2 4 ef36299 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class Complete Specification Lodged: Accepted: Published: Priority: Related Art: Name and Address of Applicant: Address for Service: NEC Home Electronics Ltd.

No. 5-24, Miyahara 3-chome Yodogawa-ku, Osaka-shi Osaka

JAPAN

Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia SComplete Specification for the invention entitled: Method of Data Retrieval from a Data Therefor The following statement is a full description best method of performing it known to me/us Base and a System of this invention, including the 5845/5 r ABSTRACT OF THE DISCLOSURE A data retrieval method and system f or searching a data f rom a data base in accordance with a word dictionary, a synonym dictionary, and/or a same concept dictionary.

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METHOD OF DATA RETRIEVAL FROM A DATA BASE AND A SYSTEM THEREFOR FIELD OF THE INVENTION The present invention relates to a method of retrieving data from a data base and a system therefor.

BACKGROUND OF THE INVENTION There has been widely utilized a data base containing large amounts of data which are sorted depending on different kinds of uses, which data are filed to be picked up easily from the data base as occasion demands. When a retrieval key 99 (or a combination of retrieval keys) corresponding to a word o a0 in data desired to pick up from the data base is entered by o an operator into an information processing apparatus, the 15 processing apparatus searches the data base by using the 9 o entered retrieval key or the combination of retrieval keys to find and pick the desired data up from the data base.

0 In a conventional method of data retrieval, however, if So the retrieval key entered into the information processing c; e o 0. 20 apparatus is not fully coincident with a word in the desired data or a part thereof, the data cannot be found and picked 0*00 ~up from the data base. For that reason, when the word of the entered retrieval key is misspelled or the operator of the information processing apparatus does not precisely remember the word in the desired data, the data cannot be retrieved or picked up from the data base.

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SUMMARY OF THE INVENTION The present invention has been made in order to eliminate a difficulty mentioned above accompanying the conventional data retrieval method and system.

Accordingly, an object of the present invention is to provide a data retrieval method and system in which desired data can be retrieved and picked up from data base even if an entered retrieval key is not completely coincident with a word in the data.

Another object of the invention is to provide a data retrieval method and system in which a misspelled retrieval S key is corrected, and a desired data can be picked up by S using synonyms for and/or words having same concept as the C word entered by an operator.

tc a In order to achieve the above and other objects, the present invention provides a data retrieval method and system aE a S whereby a retrieval key is entered into an information processing apparatus for searching the data base to retrieve as and pick up the desired corresponding data. The retrieval key entered into the information processing apparatus is ta compared with words stored in a word dictionary lIcated A within the processing apparatus: if the entered key is not coincident with any of the words in the word dictionary, the information processing apparatus processes the entered retrieval key by using a synonym dictionary and a same -2concept dictionary located within the processing apparatus, so that the processed retrieval key can be used to search the data base to retrieve and pick up the desired data.

According to the present invention, a predetermined set of words to be used as retrieval keys for retrieving data from the data base are previously stored in the word dictionary in the information processing apparatus. The retrieval key entered by an operator into the information processing apparatus is compared with the words stored in the word dictionary. If the entered retrieval key is coincident t4 with one of the words, the data base is searched using the S entered key as an actual retrieval key. If the entered Sretrieval key is not coincident with any of the words due to rT r a misspelling of the entered key, the misspelling will be corrected by replacing the letters of the entered key in tet. order to obtain a corrected retrieval key coincident with a word stored in the word dictionary. The data base is then searched using the corrected word as an actual retrieval key.

If the operator does not know the spelling of the retrieval key to be used for retrieving the data from the 4444 data base, a synonym for the key, or a word having the same ti 44 concept as the key may be entered by the operator as the effective retrieval key into the information processing C apparatus.

3- ;i In the former case, the information processing apparatus sequentially calls out synonyms as the entered retrieval key from the synonym dictionary which is located in the information processing apparatus. Then, the information processing apparatus searches the data base using each of the called-out synonyms as an actual retrieval key. In the latter case, on the other hand, if a word having the same concept as the key is entered by an operator, the information processing apparatus sequentially calls out words of the same concept as the entered word from the same concept dictionary o o located within the information processing apparatus. Then o the information processing apparatus searches the data base S0o S using each of the words of the same concept as an actual S099 b retrieval key.

The desired data can thus be reliably retrieved and picked up from the data base even if the entered retrieval key is misspelled or the operator does not know the correct spelling of the retrieval key.

i 0 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a block. diagram of an information 444.

,o processing apparatus for practicing the method and system of @4 a Sthe present invention.

Fig. 2 shows a processing flow chart of a method and system of the present invention.

4- 7 7~7~ Fig. 3 shows a flow chart of a spelling correction procedure in the method and system.

Fig. 4 shows an example of a way of writing in the work memory of the information processing apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Fig. 1 shows a block diagram of an information processing apparatus for practicing a data retrieval method and system which is one embodiment of the present invention.

As shown in Fig. i, an information processing apparatus is provided with a CPU 10 connected through a bus 12 to an input device 14 such as a keyboard for entering any data into S the information processing apparatus, to an output device 16 t i such as a cathode-ray tube display or a printer for outputting any data, and to an external memory 18 in which a data base is stored. The CPU is also connected through the bus 12 to a word dictionary memory 20 storing therein many t words and used for correcting a misspelled word which is it t entered by an operator through the input device 14, to a S synonym dictionary memory 22 previously storing synonyms of various words, to a concept dictionary memory 24 storing therein words of the same concepts, to an instruction memory c 26 storing programs for rk to be performed by the CPU Sand to a work memory 28 into which the entered correct retrieval key, synonyms and words of the same concept for use as actual retrieval keys are temporarily written as shown in Fig. 4.

The word dictionary memory 20, synonym dictionary memory 22, concept dictionary memory 24, instruction memory 26 and work memory 28 may suitably be selected from a group consisting of ROM, RAM, E-ROM, EP-ROM, read/write memory, and the like. That is, contents of these memories may appropriately be varied.

As an example of the information processing apparatus in operation, assuming now that an operator of the information processing apparatus wishes to retrieve and pick data up corresponding to a retrieval key "trolley", but since he does not know that the correct spelling is "trolley", instead he chooses "car" as the retrieval key and inputs it through the input device 14 to retrieve and pick the data up from the data base stored in the external memory 18, based upon the concept of "vehicle". Further, assuming that the operator erroneously typed "caf" into the information processing apparatus instead of "car".

t At that time, "caf" is supplied from input means 14 to CPU 10 to order the unit to search the data base, shown at 4 step SP30 in Fig. 2. As a result, the entered word "caf" is written as an entered key into the work memory 28, as shown in Fig. 4, in accordance with a data transfer program stored in the instruction memory 26, and is outputted by an output device 16 such as, for example, a display unit.

6 I I The CPU 10 then searches a word dictionary in word dictionary memory 20 in order to check whether the dictionary has a word coincident with the entered word "caf", shown at step SP31 in Fig. 2, and to e.amine the, spelling of the entered retrieval key, at step SP32. At this stage, in case that it is determined through the examination of the spelling at step SP32 that the entered retrieval key is properly spelled, that is, in case that a correct word "car" is entered by an operator, the correct word is written in the work memory 28 at step SP34 and then the data base is t searched at step SP36 to retrieve and pick up the S corresponding data using the word stored in the work memory 28 as an actual retrieval key. The data picked up from the 4 data base are supplied to the output device 16 to be displayed.

On the other hand, if it is determined through the examination of the spelling at step SP32 that the entered retrieval key is misspelled, the spelling of the entered key is corrected at step SP33 corresponding to a flow chart shown in Fig. 3.

Fig. 3 is a flow chart showing the procedure of spelling correction, whereby at step SP331 one letter of the entered retrieval key is replaced with another letter. The CPU then searches the word dictionary at step SP332 and checks whether or not the replaced word is a. proper word at step -7-

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1 'i -r r I I 04 o 4 4 4 o (I 4j I I SP333. If it is determined at step SP333 that the replaced word is not proper, for example, when the word "caf" is changed to "aaf", it is then determined at step SP334 whether or not the letters of the misspelled retrieval key has already been replaced with all other possible letters. If not at this step, steps SP331 and SP332 are repeated and subsequently the word "caf" is changed to "baf" in the next replacing operation.

If it is determined at step SP333 that the replaced word 10 is proper, for example, when "caf" is changed to "cap" the ,proper word is written in the work memory 28 at step SP335 as Sa retrieval key candidate as shown in Fig. 4. Such a write in the memory 28 is repeated tnrough step SP334 until all of t the possible letters have been replaced. As a result, a plurality of the retrieval key candidates may be written in the work memory 28 and displayed to the output device 16.

Further, when all of the possible letters of the entered word have been replaced, the CPU 10 proceeds from step SP334 to step SP336, whereby the adjacent letters of the misspelled retrieval key are interchanged with each other, for example, "caf" is changed to "acf". The interchanged word is then compared with the words stored in the word dictionary memory at step SP337. It is then determined whether or not the interchanged word is proper at step SP338. If it is proper word, namely, a coincident word has previously been stored Qt 8444 4 4 $4 4 44 t 4 t4 J. i

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e 44 4I 444 *r I 4 4 8 c.; t t in the word dictionary memory 20, then the properly interchanged word is stored in the work memory 28 as a further retrieval key candidate at step SP339. This interchanging steps repeat until all of the possible interchanges are obtained through step SP340 and the retrieval key candidates written in the work memory 28 may be added. These interchanging stePs would correct errors caused by reversing keys while typing a word. After that, it is determined whether or not there is any retrieval key candidate in the work memory 28 at step 4 ,When there are retrieval key candidates in the work 4. 4 4 I t e memory 28, the CPU then searches the data base at step SP36 44 to retrieve and pick up the data using each of the retrieval key candidates written in the work memory 28. In case that when it is determined that there is no retrieval key candidate in the work memory 28 at step SP35, then the 4 retrieval operation will end and, accordingly, the operator

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may enter a new key through the input device 14 if necessary.

If it is determined at step SP37 that the desired data is picked up, then the retrieval operation will end and the Ict data are displayed or printted out by the output device 16.

On the other hand, if it is determined at step SP37 that still the desired data is not picked up, then the CPU searches a synonym dictionary in synonym dictionary memory 22 to perform retrieval in terms of synonyms at steps SP38 and 9

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SP39. In this case, the CPU 10 checks whether or not a synonym for each of the retrieval key candidates written in the work memory 28, for example the proper words "cap", "car" and "cat" shown in Fig. 4 exists in the synonym dictionary.

S 5 When CPU 10 has found a synonym for the key candidate in the synonym dictionary, the synonym is read out at step SP38 from the synonym dictionary and then written into a synonym block of the work memory 28 as a retrieval candidate as shown in Fig. 4. The synonym written in the work memory 28 may be outputted by the output device 16. The CPU then searches the data base at step SP39 to retrieve and pick up the data using each of the retrieval key candidates written 4 in the synonym block of the work memory 28.

If the desired data can be picked up from the data base at step SP40, then the retrieval operation ends. On the to* other hand, if the desired. data is still not picked up, then the CPU 10 proceeds steps SP41 and SP42 whereby performing a retrieval operation using the "same concept" method.

S° A same concept dictionary stored in concept dictionary memory 24 is used nearly in the same manner as the retrieval with the synonyms described above. That is, at step SP41 the CPU 10 sequentially calls out words from the concept dictionary memory 24 having the same concept as each of the proper words written in the work memory 28 such as "cap", "car" and "cat" and writes them in a same concept block of 10

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the work memory 28 as retrieval key candidates as shown in Fig. 4.

Then, the data base is searched at step SP42 with each of the retrieval key candidates written in the same concept block of the work memory 28 to retrieve and oick up the data.

The data read out of the data base Lre then displayed or printted out by the output device 16. Then it is determined at step SP43 whether or not the desired data is picked up from the data base.

As described above, the entered retrieval key is checked with by a word dictionary and the synonyms for and the words having the same concept as the entered word are subsequently f It f found out. However, the present invention is not limited ft n thereto or thereby. That is, the method and system of the present invention may be varied such that the steps are interchanged with each other or may be omitted. For example, the retrieval operation in terms of synonym step SP39 may be performed after the retrieval using the same concept method f, step SP42. Further, the retrieval using the same concept may be performed immediately after checking the spelling of the entered retrieval key while the synonym step is not

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e performed.

Moreover, the operator may select the desired word or key from the retrieval key candidates written in the work memory 28. In this case, immediately after the misspelled 1 f ^.j

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key "caf", for example, is corrected to "car", the data base will be searched to retrieve and pick up the desired data by using the appropriate retrieval key "trolley" which is selected by the operator from the retrieval key candidates s writ Len in the work memory 28 through the retrieval operation of the same concept with respect merely to the word "car".

As described above, even if the operator enters the misspelled retrieval key or does not exactly know the word in S0", the data desired to be retrieved, the synonym for the word or S0.iO2 the word of the same concept as the former can be employed 0 thereby easily retrieving the desired data from the data o o 1 Goo base.

Therefore, according to the present invention, desired data can reliably be retrieved and picked up from a data base 0° I even if a misspelled retrieval key is entered or a correct o retrieval key is not known.

o While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

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Claims (26)

1. A method for retrieving data from a data base by an information processing apparatus, comprising the steps of: entering a retrieval key into said information processing apparatus; comparing the retrieval key with words in a word dictionary located within said information processing apparatus; o'W".c writing the retrieval key in a temporary memory if the entered retrieval key is coincident with a word in said word o *9 dictionary; correcting a spelling of the entered retrieval key if the key is not coincident with any words in said word *1 dictionary, and writing the corrected keys into said i temporary memory; searching the data base to retrieve desired data on the basis of the retrieval keys written in said temporary memory.

2. A method of Claim 1, further comprising the steps c4OI 20 of: searching a synonym dictionary on the basis of the retrieval keys written in said temporary memory; writing synonyms into a synonym block of said temporary memory; 13 1 I I 00 o t i t t r S *i t o t .4 0 0~ 00r searching the data base to retrieve the desired data on the basis of the retrieval keys written in said synonym block of said temporary memory.

3. A method of Claim 1 or 2, further comprising the steps of: searching a concept dictionary on the basis of the retrieval keys written in said temporary memory; writing words having the same concept as said retrieval keys into a concept block of said temporary memory; searching the data base to retrieve the data with the retrieval keys written in said concept block of said temporary memory.

4. A method according to claim 1, wherein a predetermined set of words to be used as said retrieval key 1i for retrieving data from the data base are previously stored in the word dictionary.

5. A method according to claim 4, wherein said retrieval key has a first letter at F beginning of said retrieval key, said correcting the spelling step comprising ao the steps of: (1)replacing the first letter with a next letter, thereby forming a modified key; (2)if said modified key is coincident with a word in said word dictionary, performing step .004 00 0 0 j. 1 14 I (3)if said modified key has not yet had said first letter replaced with all possible letters, performing step (4)defining a second letter as said first letter; (5)interchanging said second letter of said retrieval key with a next adjacent letter, thereby forming said modified key; (6)if said modified key is coincident with a word in said word dictionary, performing step (7)if said next adjacent letter is not a last letter of S said retrieval key, performing step wherein said second letter is reassigned as said next adjacent letter; and (8)defining said desired spelling as said modified key.

6. A method as recited in claim 3, wherein said t t S modified keys formed after each step of said spell correcting step are stored in said temporary memory in said information processing apparatus.

7. In an information processing apparatus, a data retrieval method for correcting an entered retrieval key so *20 as to search the data base, comprising the steps of: (a)entering the retrieval key into the information processing apparatus; (b)comparing the retrieval key with words in a word dictionary located within said processing apparatus; 9' 15 (c)executing a spell correction step on said retrieval key to obtain a desired spelling when sai.d retrieval key is not coincident with any of said words in said word dictionary; (d)performing one of the following two steps if said desired spelling is not coincident to a word in said word dictionary: searching for a synonym for said retrieval key in a synonym dictionary, or searching for a word having a same concept as said retrieval key in a same concept dictionary; o0: (e)performing the other of said two steps if said one step does not return a value coincident to a word in said 9 word dictionary; and 0 (f)if the method determines a desired word coincident with a word in said word dictionary, searching the data base l1 on the basis of the desired word to retrieve desired data. 0 00 0

8. A method according to claim 7, wherein said 0 retrieval key has a first letter at a beginning of said retrieval key, said spell correction step comprising the .09 steps of: "2o4 (1)replacing the first letter with a next letter, thereby forming a modified key; (2)if said modified key is coincident with a word in said word dictionary, performing step (3)if said modified key has not yet had said first letter replaced with all possible letters, performing step 16 j 1 (4)defining a second letter as said first letter; said second letter of said retrieval key with a next adjacent letter, thereby forming said modified key; (6)if said modified key is coincident with a word in said word dictionary, performing step (7)if said next adjacent letter is not a last letter of said retrieval key, performing step wherein said second t letter is reassigned as said next adjacent letter; and (8)defining said desired spelling as said modified key. s

9. A method as recited in claim 8, wherein said Ir r. modified keys formed after each step of said spelling step are stored in a temporary memory in said information processing apparatus.

A method as recited in claim 9, wherein said retrieval key is assigned to a synonym search key, said searching for said synonym step comprising the steps of: (a)retrieving a first synonym for said synonym search tao key from said synonym dictionary; (b)if there are any other synonyms for said synonym search key in said synonym dictionary, performing step wherein one of said any other synonyms is assigned to said first synonym; 17 I i I 1 (c)assigning one of said plurality of modified keys from said temporary memory to said synonym search key; (d)if said one of said plurality of modified keys has not been previously assigned to said synonym search key, performing step and (e)assigning said first synonym to said synonym.

11. A method as claimed in claim 9, wherein said retrieval key is assigned to a same concept search key, said o same concept word searching step comprising the steps of: 4 lp4 (i)retrieving a first same concept word for said same concept search key from said same concept dictionary; (ii) if there are any other words having said same concept for said same concept search key in said same concept dictionary, performing step wherein one of said any S t i other words having said same concept is assigned to said *4 first same concept word; a *0 a.g 6 (iii)assigning one of said plurality of modified keys from said temporary memory to said same concept search key; (iv)if said one of said plurality of modified keys has not been previously assigned to said same concept search key, performing step and (v)assigning said first same concept word to said word having the same concept as said retrieval key.

12. A data retrieval method for searching a data base in response to an entered retrieval key, the method -18 b*L. comprising the steps of: comparing said retrieval key with words in a word dictionary located within said processing apparatus; if said retrieval key is not coincident with any of said Swords in said word dictionary, processing said retrieval key using at least one of said word dictionary, a synonym dictionary and a same concept dictionary, thereby generating a processed retrieval key; and 0 searching said data base on the basis of said processed S10 retrieval key. o I~ e S"

13. A method according to claim 12, wherein said processing step comprises the steps of: SI performing one of the following two steps: searching for a synonym for said retrieval key in a 1 synonym dictionary, or searching for a word having a same concept as said retrieval key in a same concept dictionary; and performing the other of said two steps if said one step does not return a value coincident to a word in said word 20 dictionary.

14. A method according to claim 13, further comprising the step of executing a spell correction step on said retrieval key to obtain a desired spelling when said retrieval key is not coincident with any of said words in said word dictionary, said spell correction step occurring 19 b 'n before said performing one of two steps, said performing one of two steps occurring only if said desired spelling is not coincident to a word in said word dictionary.

A system for retrieving data from a data base, comprising: means for storing the data base; means for entering a retrieval key for searching the data base to retrieve desired data; means for outputting said entered retrieval key and the data retrieved from the data base in accordance with said retrieval key; means for controlling the retrieving system; memory means for storing dictionaries, said memory means being utilized for processing said entered retrieval key thereby obtaining actual retrieval keys on the basis of which said data base is searched; ft means for correcting an incorrect retrieval key; 11,i5 means for storing programs according to which said controlling means "t performs; and I II ,means for connecting said controlling means to said data base storing f means, said retrieval key entering means, said outputting means, and said memory means.

16. A system of claim 15, wherein said retrieval key processing means comprises: means for storing a word dictionary thereby comparing said entered ff0" retrieval key with a word stored in said word o I t aa e dictionary; and means for writing said entered retrieval key which is coincident with said word in said word dictionary.

17. A system of Claim 15 or 16, wherein said memory means comprises: means for storing a synonym dictionary; and means for writing actual retrieval key candidates which are synonyms of said entered retrieval key, said retrieval oZ key candidates are read out of said synonym dictionary. t

18. A system of Claim 15, 16 or 17, wherein said memory means comprises: means for storing a concept dictionary; and means for writing actual retrieval key candidates which have the same concept as said entered retrieval key, said retrieval key candidates are read out of said concept dictionary.

19. A system of Claim 15, wherein contents of said memory means are varied.

,20. A system of Claim 19, wherein said memory means is selected from a group consisting of ROM, RAM, E-ROM, EP-ROM and read/write memory.

21. A system of Claim 15, wherein said retrieval key entering means is a keyboard.

22. A system of Claim 15, wherein said outputting means is a display. 21 .J 1

23. A system of Claim 15, wherein said outputting means is a CRT.

24. A system of Claim 15, wherein said outputting means is a printer.

25. A system of Claim 15, wherein said controlling means comprises at least one central processing unit.

26. A system of Claim 25, wherein said controlling means comprises two central processing units. t DATED this EIGHTEENTH day of MAY, 1989 c NEC Home Electronics Ltd. C *t i 2 Patent Attorneys for the Applicant SPRUSON FERGUSON 22 I It I