postgresql - Postgres中字符串的词频？

Question

是否可以从 Postgres 中包含文本字符串的字段中识别不同的单词并为每个单词计数？

Answer 1

是这样的吗？

SELECT some_pk,        regexp_split_to_table(some_column, '\s') as wordFROM some_table

然后很容易得到不同的词:

SELECT DISTINCT wordFROM (   SELECT regexp_split_to_table(some_column, '\s') as word  FROM some_table) t

或获取每个单词的计数:

SELECT word, count(*)FROM (   SELECT regexp_split_to_table(some_column, '\s') as word  FROM some_table) tGROUP BY word