JPS62241026A - Character string retrieving system - Google Patents

Abstract

PURPOSE:To shorten the executing time of a character string retrieving program by deciding a single character having the minimum using frequency out of a retrieved character string and retrieving and selecting the data to be retrieved with use of said decided character to decrease the comparison frequency between the retrieved character string and the data to be retrieved. CONSTITUTION:A using character analyzing means 1 reads the data 100 to be retrieved and analyzes it to deliver the using character distribution data 200. The emerging frequency of each character of the data 100 is recorded to the data 200. A deciding means 20 of a character string retrieving means 2 decides a single character having the minimum using frequency out of a retrieved character string 300 based on the data 200. Then a retrieving means 21 reads the data 100 and performs the retrieval with the single character decided by the means 20 and to be retrieved first to select the data to be retrieved. A comparison means 22 compares the data to be retrieved that is selected by the means 21 with the character string 300 and delivers the retrieved data 400 when the coincidence is obtained through said comparison.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a character string search method, and particularly to a character string search method in a computer system.

[Conventional technology]

Conventionally, in this type of string search method, the first character of the search string is sequentially compared from the beginning of the searched data as a method to search for data containing certain string data from data stored in a file. Then, the entire search string was compared from the position where the same character was detected to see if it matched the condition.

[Problem that the invention seeks to solve]

In the conventional string search method described above, the execution time of the string search program is proportional to the number of executed instructions and the number of characters referenced during execution. If there are few character strings that match the conditions, unnecessary command execution and character references will be performed, resulting in a disadvantage that the execution time of the character string search program will be longer.

In view of the above-mentioned points, an object of the present invention is to provide a character string search method that can shorten the execution time of a character string search program.

Means for Solving Problem C] The character string search method of the present invention is a character string search method that inputs data stored in a file, searches for specified character strings under specified conditions, and searches for data that matches the conditions. a used character distribution analysis means for inputting searched data and analyzing the used character distribution to create used character distribution data; and a character string search means for performing a conditional search for character strings in the data.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

The figure is a block diagram showing one embodiment of the present invention.

The character string search method of this embodiment uses the usage character distribution analysis means 1.
, character string search means 2 , searched data 100 , used character distribution data 200 , search character string 300 , and searched data 400 .

The character string search means 2 includes a determining means 20 that determines one character to be searched first based on used character distribution data 200, and a retrieval means that searches the searched data 100 using the one character determined by the determining means 20. 21, and a comparison means 22 that compares the data searched by the search means 21 with the search character string 300 and outputs the searched data 400.

Next, the operation of the character string search method of this embodiment configured as described above will be explained.

First, the usage character distribution analysis means 1 analyzes the search target data 100.
Read and analyze this to obtain usage character distribution data 200
Output. In the used character distribution data 200, the appearance frequency of each character in the searched data 100 is recorded. In this embodiment, for example, the character A is 1%, the character B is 3%, the character C is 5%, etc. is recorded.

The determining means 20 determines the least frequently used character in the search string 300 based on the used character distribution data 200. In this embodiment, for example, the search string is rABCJ.
The character rAJ is determined when .

If one character that is not in the used character distribution data 200 is specified as the search character string 300, the search character string 300 does not exist without searching the searched data 100.

Next, the search means 21 reads the searched data 100 and selects the first search item determined by the determination means 20.
Search by character and select the data to be searched.

The comparison means 22 compares the search target data selected by the search means 21 with the search character string 300, and outputs the data matching the conditions as searched data 400.

〔Effect of the invention〕

As explained above, the present invention analyzes the distribution of characters existing in the searched data, determines the least frequently used character in the search string based on the analysis result, and By searching the search data, selecting the searched data to be compared with the search string, and reducing the number of comparisons between the search string and the searched data, the effective time of the string search program can be shortened. be. This is particularly effective when searching for searched data using multiple search strings.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. In the figure, 1...Used character distribution analysis means, 2... Character string search means, 2σ...Decision means, 21... search means, 22... Comparison means, 100...searched data, 200...Character distribution data used, 300...Search string, 400...Retrieved data.

Claims (1)

[Claims] In a character string search method in which data stored in a file is input and a specified character string is checked under specified conditions to search for data that matches the conditions, the data to be searched is input and the distribution of characters used is determined. Character usage distribution analysis means for analyzing and creating usage character distribution data, and character strings for performing a conditional search for character strings in the search target data based on the usage character distribution data created by the usage character distribution analysis means. A character string search method comprising: a search means;