PostgreSQL的扩展dict_int应用案例解析

-- 安装扩展
CREATE EXTENSION dict_int;
-- 验证安装
SELECT extname FROM pg_extension WHERE extname = 'dict_int';

CREATE TEXT SEARCH DICTIONARY intdict (
    TEMPLATE = dict_int,
    -- 可选参数
    MAXLEN = 10,       -- 最大整数位数(默认无限制)
    REJECTLONG = true  -- 是否拒绝过长整数(默认false)
);

-- 创建只接受5位以内整数的字典
CREATE TEXT SEARCH DICTIONARY intdict_5digit (
    TEMPLATE = dict_int,
    MAXLEN = 5,
    REJECTLONG = true
);
-- 创建接受所有整数的字典
CREATE TEXT SEARCH DICTIONARY intdict_all (
    TEMPLATE = dict_int
);

-- 创建包含整数字典的配置
CREATE TEXT SEARCH CONFIGURATION mycfg (COPY = simple);
ALTER TEXT SEARCH CONFIGURATION mycfg
    ALTER MAPPING FOR int, uint WITH intdict;

-- 测试字典效果
SELECT ts_lexize('intdict', '12345');  -- 返回: {12345}
SELECT ts_lexize('intdict', 'abc123'); -- 返回: {} (只匹配纯整数)
-- 在查询中使用
SELECT * FROM documents 
WHERE to_tsvector('mycfg', content) @@ to_tsquery('mycfg', '123');

-- 配置专门处理产品编号的搜索
CREATE TEXT SEARCH CONFIGURATION product_search (COPY = simple);
ALTER TEXT SEARCH CONFIGURATION product_search
    ALTER MAPPING FOR int, uint WITH intdict_5digit, simple;
-- 查询示例
SELECT * FROM products
WHERE to_tsvector('product_search', product_code) @@ '12345';

-- 配置日志分析搜索(包含状态码和消息)
CREATE TEXT SEARCH CONFIGURATION log_search (COPY = simple);
ALTER TEXT SEARCH CONFIGURATION log_search
    ALTER MAPPING FOR int, uint WITH intdict,
    ALTER MAPPING FOR asciiword WITH english_stem;
-- 查询状态码200的日志
SELECT * FROM server_logs
WHERE to_tsvector('log_search', log_message) @@ '200';