BareSQL v0.2.0

BareSQL Portable gets a rule for every difference the 0.1.0 README listed
without one: 11 new rules, 69 in all. Each was run on SQLite, PostgreSQL,
MySQL and MariaDB, and CI runs them again on every engine version it tests.

• alter-column: 21 forms of ALTER TABLE, each with the engines that
  refuse it: ALTER COLUMN ... TYPE and SET/DROP NOT NULL (PostgreSQL only),
  MODIFY and CHANGE (MySQL and MariaDB only), ALTER COLUMN ... SET or DROP
  DEFAULT, several actions in one statement, ADD/DROP CONSTRAINT, ADD
  INDEX, DROP CHECK, DROP INDEX/PRIMARY KEY/FOREIGN KEY, ADD COLUMN IF NOT
  EXISTS, DROP COLUMN IF EXISTS or CASCADE, ALTER TABLE IF EXISTS, AFTER
  and FIRST, RENAME without TO, RENAME a TO b without COLUMN, and the
  ALGORITHM and LOCK options.
• reserved-word: names that are reserved words on some engines (rank,
  key, user, groups, row and 78 more), wherever lint can tell a word is a
  name. After AS in a select list, where PostgreSQL takes any word, only
  the other engines count.
• aggregate-filter: COUNT(*) FILTER (WHERE ...), which MySQL and MariaDB
  lack.
• from-dual: FROM DUAL, which SQLite and PostgreSQL lack.
• trim-from: TRIM(LEADING/TRAILING/BOTH ... FROM ...) and TRIM(x FROM s),
  which SQLite lacks, and the two-argument TRIM, LTRIM and RTRIM, which
  MySQL and MariaDB lack.
• substring-from: SUBSTRING(s FROM a FOR b), which SQLite lacks, the
  FOR-only form and SUBSTR ... FROM, and SUBSTRING(s FROM 'pattern'), a
  regular expression on PostgreSQL only.
• drop-cascade: DROP TABLE ... CASCADE or RESTRICT; SQLite refuses both,
  and MySQL and MariaDB ignore CASCADE.
• cast-to-float: CAST to DOUBLE PRECISION or REAL (MariaDB refuses),
  DOUBLE (PostgreSQL refuses) and FLOAT (4 bytes on MySQL and MariaDB).
• avg-digits: AVG of integers or decimals has 4 more decimal places than
  the values on MySQL and MariaDB and about 16 digits elsewhere; averages
  that are rounded or compared aren't flagged.
• round-half: ROUND of a floating point half rounds away from zero on
  SQLite and to even elsewhere, PostgreSQL has no ROUND(float, n), and
  SQLite rounds decimals to digits through a binary float (ROUND(0.15, 1)
  is 0.1 there and 0.2 elsewhere).
• group-case (a note, as it depends on the data): GROUP BY, DISTINCT,
  COUNT(DISTINCT), UNION, INTERSECT and EXCEPT over text merge 'x'
  and 'X' on MySQL and MariaDB.

Fixed in older rules: table-options no longer flags ON UPDATE CASCADE
after a REFERENCES clause in a column definition, and lint looks up a
column correctly when a statement names the same table twice.

Also: the README links each release archive directly
(releases/latest/download).