sql - Using python psychopg2 to get a count on all variables in the database that contain a specific string -


i have list, words = [word1, word2, word3, ...] want use sql return number of times each word appears in column of sql file. can't figure out how pass variable sql query. appreciated! code far looks like:

import psycopg2 sql  word in words     conn = sql.connect(**params)    c = conn.cursor()         #create query , parameters usernames , ids     query = """ select count(column a) file             column similar '% **variable word** %'              limit 1000; """      try:        c.execute(query)     except:        conn.commit()        print("error in query")     result = c.fetchall()

also, count return total number of times word appears or number of lines of column in appears? (will count of in "the team won game" return 1 or two?)

the replaceable parameter flag used psycopg2 "%s", , use plain "%" in query replaceable parameters need double (i.e., "%%"). code should like:

 query = """select count(column_a) file         column_a similar '%%%s%%'         limit 1000;""" try:    c.execute(query, word)

this should return number of lines in word appears, not total number of occurrences of word in lines.

your example has space in column name used; i've substituted underscore, if column name contains space, name should double-quoted in query.


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