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The SQL standard specifies a huge number of keywords which may not be used as the names of tables, indices, columns, databases, user-defined functions, collations, virtual table modules, or any other named object. The list of keywords is so long that few people can remember them all. For most SQL code, your safest bet is to never use any English language word as the name of a user-defined object.
If you want to use a keyword as a name, you need to quote it. There are three ways of quoting keywords in SQLite:
'keyword' A keyword in single quotes is a string literal. "keyword" A keyword in double-quotes is an identifier. [keyword] A keyword enclosed in square brackets is an identifier. This is not standard SQL. This quoting mechanism is used by MS Access and SQL Server and is included in SQLite for compatibility. `keyword` A keyword enclosed in grave accents (ASCII code 96) is an identifier. This is not standard SQL. This quoting mechanism is used by MySQL and is included in SQLite for compatibility.
For resilience when confronted with historical SQL statements, SQLite will sometimes bend the quoting rules above:
If a keyword in single quotes (ex: 'key' or 'glob') is used in a context where an identifier is allowed but where a string literal is not allowed, then the token is understood to be an identifier instead of a string literal.
If a keyword in double quotes (ex: "key" or "glob") is used in a context where it cannot be resolved to an identifier but where a string literal is allowed, then the token is understood to be a string literal instead of an identifier.
Programmers are cautioned not to use the two exceptions described in the previous bullets. We emphasize that they exist only so that old and ill-formed SQL statements will run correctly. Future versions of SQLite might change to raise errors instead of accepting the malformed statements covered by the exceptions above.
SQLite adds new keywords from time to time when it takes on new features. So to prevent your code from being broken by future enhancements, you should normally quote any identifier that is an English language word, even if you do not have to.
The list below shows all possible keywords used by any build of SQLite regardless of compile-time options. Most reasonable configurations use more or all of these keywords, but some keywords may be omitted when SQL language features are disabled. Regardless of the compile-time configuration, any identifier that is not on the following 121 element list is not a keyword to the SQL parser in SQLite:
ABORT
ACTION
ADD
AFTER
ALL
ALTER
ANALYZE
AND
AS
ASC
ATTACH
AUTOINCREMENT
BEFORE
BEGIN
BETWEEN
BY
CASCADE
CASE
CAST
CHECK
COLLATE
COLUMN
COMMIT
CONFLICT
CONSTRAINT
CREATE
CROSS
CURRENT_DATE
CURRENT_TIME
CURRENT_TIMESTAMP
DATABASE
DEFAULT
DEFERRABLE
DEFERRED
DELETE
DESC
DETACH
DISTINCT
DROP
EACH
ELSE
END
ESCAPE
EXCEPT
EXCLUSIVE
EXISTS
EXPLAIN
FAIL
FOR
FOREIGN
FROM
FULL
GLOB
GROUP
HAVING
IF
IGNORE
IMMEDIATE
IN
INDEX
INDEXED
INITIALLY
INNER
INSERT
INSTEAD
INTERSECT
INTO
IS
ISNULL
JOIN
KEY
LEFT
LIKE
LIMIT
MATCH
NATURAL
NO
NOT
NOTNULL
NULL
OF
OFFSET
ON
OR
ORDER
OUTER
PLAN
PRAGMA
PRIMARY
QUERY
RAISE
REFERENCES
REGEXP
REINDEX
RELEASE
RENAME
REPLACE
RESTRICT
RIGHT
ROLLBACK
ROW
SAVEPOINT
SELECT
SET
TABLE
TEMP
TEMPORARY
THEN
TO
TRANSACTION
TRIGGER
UNION
UNIQUE
UPDATE
USING
VACUUM
VALUES
VIEW
VIRTUAL
WHEN
WHERE
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