How do I use regex in a SQLite query?

Question

I\'d like to use a regular expression in sqlite, but I don\'t know how.

My table has got a column with strings like this: \"3,12,13,14,19,28,32\" Now if I type \"whe

Answer 1

my solution in python with sqlite3:

   import sqlite3
   import re

   def match(expr, item):
        return re.match(expr, item) is not None

   conn = sqlite3.connect(':memory:')
   conn.create_function("MATCHES", 2, match)
   cursor = conn.cursor()
   cursor.execute("SELECT MATCHES('^b', 'busy');")
   print cursor.fetchone()[0]

   cursor.close()
   conn.close()

if regex matches, the output would be 1, otherwise 0.

Answer 2

You may consider also

WHERE x REGEXP '(^|\D{1})3(\D{1}|$)'

This will allow find number 3 in any string at any position

Answer 3

In case if someone looking non-regex condition for Android Sqlite, like this string [1,2,3,4,5] then don't forget to add bracket([]) same for other special characters like parenthesis({}) in @phyatt condition

WHERE ( x == '[3]' OR
        x LIKE '%,3]' OR
        x LIKE '[3,%' OR
        x LIKE '%,3,%');

Answer 4

An exhaustive or'ed where clause can do it without string concatenation:

WHERE ( x == '3' OR
        x LIKE '%,3' OR
        x LIKE '3,%' OR
        x LIKE '%,3,%');

Includes the four cases exact match, end of list, beginning of list, and mid list.

This is more verbose, doesn't require the regex extension.

Answer 5

In Julia, the model to follow can be illustrated as follows:

using SQLite
using DataFrames

db = SQLite.DB("<name>.db")

register(db, SQLite.regexp, nargs=2, name="regexp")

SQLite.Query(db, "SELECT * FROM test WHERE name REGEXP '^h';") |> DataFrame