什么是高级?这就叫高级—openGauss(320)

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#openGauss #入门 #安装 #数据库 #开源

知识来源:docs-opengauss.osinfra.cn/zh/

搜索表

在不使用索引的情况下也可以进行全文检索。

  • 一个简单查询:将body字段中包含america的每一行打印出来。

    openGauss=# DROP SCHEMA IF EXISTS tsearch CASCADE;
    
    openGauss=# CREATE SCHEMA tsearch;
    
    openGauss=# CREATE TABLE tsearch.pgweb(id int, body text, title text, last_mod_date date);
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(1, 'China, officially the People''s Republic of China (PRC), located in Asia, is the world''s most populous state.', 'China', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(2, 'America is a rock band, formed in England in 1970 by multi-instrumentalists Dewey Bunnell, Dan Peek, and Gerry Beckley.', 'America', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(3, 'England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west.', 'England', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(4, 'Australia, officially the Commonwealth of Australia, is a country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands.', 'Australia', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(6, 'Japan is an island country in East Asia.', 'Japan', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(7, 'Germany, officially the Federal Republic of Germany, is a sovereign state and federal parliamentary republic in central-western Europe.', 'Germany', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(8, 'France, is a sovereign state comprising territory in western Europe and several overseas regions and territories.', 'France', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(9, 'Italy officially the Italian Republic, is a unitary parliamentary republic in Europe.', 'Italy', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(10, 'India, officially the Republic of India, is a country in South Asia.', 'India', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(11, 'Brazil, officially the Federative Republic of Brazil, is the largest country in both South America and Latin America.', 'Brazil', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(12, 'Canada is a country in the northern half of North America.', 'Canada', '2010-1-1');
    
    openGauss=# INSERT INTO tsearch.pgweb VALUES(13, 'Mexico, officially the United Mexican States, is a federal republic in the southern part of North America.', 'Mexico', '2010-1-1');
    
    openGauss=# SELECT id, body, title FROM tsearch.pgweb WHERE to_tsvector('english', body) @@ to_tsquery('english', 'america');
     id |                                                          body                                                           |  title  
    ----+-------------------------------------------------------------------------------------------------------------------------+---------
      2 | America is a rock band, formed in England in 1970 by multi-instrumentalists Dewey Bunnell, Dan Peek, and Gerry Beckley. | America
     12 | Canada is a country in the northern half of North America.                                                              | Canada
     13 | Mexico, officially the United Mexican States, is a federal republic in the southern part of North America.              | Mexico
     11 | Brazil, officially the Federative Republic of Brazil, is the largest country in both South America and Latin America.   | Brazil
    (4 rows)
    

    像America这样的相关词也会被找到,因为这些词都被处理成了相同标准的词条。

#openGauss #入门 #安装 #数据库 #开源

知识来源:docs-opengauss.osinfra.cn/zh/