32 KiB
slug | sidebar_position | sidebar_label |
---|---|---|
/en/sql-reference/functions/url-functions | 200 | URLs |
Functions for Working with URLs
:::note
The functions mentioned in this section are optimized for maximum performance and for the most part do not follow the RFC-3986 standard. Functions which implement RFC-3986 have RFC
appended to their function name and are generally slower.
:::
You can generally use the non-RFC
function variants when working with publicly registered domains that contain neither user strings nor @
symbols.
Below table below details which symbols in an URL can (✔
) or cannot (✗
) be parsed by the respective RFC
and non-RFC
variants:
Symbol | non-RFC |
RFC |
---|---|---|
' ' | ✗ | ✗ |
\t | ✗ | ✗ |
< | ✗ | ✗ |
> | ✗ | ✗ |
% | ✗ | ✔* |
{ | ✗ | ✗ |
} | ✗ | ✗ |
| | ✗ | ✗ |
\\ | ✗ | ✗ |
^ | ✗ | ✗ |
~ | ✗ | ✔* |
[ | ✗ | ✗ |
] | ✗ | ✔ |
; | ✗ | ✔* |
= | ✗ | ✔* |
& | ✗ | ✔* |
symbols marked *
are sub-delimiters in RFC 3986 and allowed for user info following the @
symbol.
Functions that Extract Parts of a URL
If the relevant part isn’t present in a URL, an empty string is returned.
protocol
Extracts the protocol from a URL.
Examples of typical returned values: http, https, ftp, mailto, tel, magnet.
domain
Extracts the hostname from a URL.
Syntax
domain(url)
Arguments
url
— URL. Type: String.
The URL can be specified with or without a protocol. Examples:
svn+ssh://some.svn-hosting.com:80/repo/trunk
some.svn-hosting.com:80/repo/trunk
https://clickhouse.com/time/
For these examples, the domain
function returns the following results:
some.svn-hosting.com
some.svn-hosting.com
clickhouse.com
Returned values
- Host name if ClickHouse can parse the input string as a URL, otherwise an empty string. String.
Example
SELECT domain('svn+ssh://some.svn-hosting.com:80/repo/trunk');
┌─domain('svn+ssh://some.svn-hosting.com:80/repo/trunk')─┐
│ some.svn-hosting.com │
└────────────────────────────────────────────────────────┘
domainRFC
Extracts the hostname from a URL. Similar to domain, but RFC 3986 conformant.
Syntax
domainRFC(url)
Arguments
url
— URL. Type: String.
Returned values
- Host name if ClickHouse can parse the input string as a URL, otherwise an empty string. String.
Type: String
.
Example
SELECT
domain('http://user:password@example.com:8080/path?query=value#fragment'),
domainRFC('http://user:password@example.com:8080/path?query=value#fragment');
┌─domain('http://user:password@example.com:8080/path?query=value#fragment')─┬─domainRFC('http://user:password@example.com:8080/path?query=value#fragment')─┐
│ │ example.com │
└───────────────────────────────────────────────────────────────────────────┴──────────────────────────────────────────────────────────────────────────────┘
domainWithoutWWW
Returns the domain and removes no more than one ‘www.’ from the beginning of it, if present.
topLevelDomain
Extracts the the top-level domain from a URL.
topLevelDomain(url)
Arguments
url
— URL. String.
:::note The URL can be specified with or without a protocol. Examples:
svn+ssh://some.svn-hosting.com:80/repo/trunk
some.svn-hosting.com:80/repo/trunk
https://clickhouse.com/time/
:::
Returned values
- Domain name if ClickHouse can parse the input string as a URL. Otherwise, an empty string. String.
Example
Query:
SELECT topLevelDomain('svn+ssh://www.some.svn-hosting.com:80/repo/trunk');
Result:
┌─topLevelDomain('svn+ssh://www.some.svn-hosting.com:80/repo/trunk')─┐
│ com │
└────────────────────────────────────────────────────────────────────┘
topLevelDomainRFC
Extracts the the top-level domain from a URL. It is similar to topLevelDomain, but conforms to RFC 3986.
topLevelDomainRFC(url)
Arguments
url
— URL. String.
:::note The URL can be specified with or without a protocol. Examples:
svn+ssh://some.svn-hosting.com:80/repo/trunk
some.svn-hosting.com:80/repo/trunk
https://clickhouse.com/time/
:::
Returned values
- Domain name if ClickHouse can parse the input string as a URL. Otherwise, an empty string. String.
Example
Query:
SELECT topLevelDomain('http://foo:foo%41bar@foo.com'), topLevelDomainRFC('http://foo:foo%41bar@foo.com');
Result:
┌─topLevelDomain('http://foo:foo%41bar@foo.com')─┬─topLevelDomainRFC('http://foo:foo%41bar@foo.com')─┐
│ │ com │
└────────────────────────────────────────────────┴───────────────────────────────────────────────────┘
firstSignificantSubdomain
Returns the “first significant subdomain”. The first significant subdomain is a second-level domain if it is ‘com’, ‘net’, ‘org’, or ‘co’. Otherwise, it is a third-level domain. For example, firstSignificantSubdomain (‘https://news.clickhouse.com/’) = ‘clickhouse’, firstSignificantSubdomain (‘https://news.clickhouse.com.tr/’) = ‘clickhouse’
. The list of “insignificant” second-level domains and other implementation details may change in the future.
Syntax
firstSignificantSubdomain(URL)
Arguments
url
— URL. String.
Returned value
- The first significant subdomain. String.
Example
Query:
SELECT firstSignificantSubdomain('http://www.example.com/a/b/c?a=b')
Result:
┌─firstSignificantSubdomain('http://www.example.com/a/b/c?a=b')─┐
│ example │
└───────────────────────────────────────────────────────────────┘
firstSignificantSubdomainRFC
Returns the “first significant subdomain”. Similar to firstSignficantSubdomain but according to RFC 1034.
Syntax
firstSignificantSubdomainRFC(url)
Arguments
url
— URL. String.
Returned value
- The first significant subdomain. String.
Example
Query:
SELECT
firstSignificantSubdomain('http://user:password@example.com:8080/path?query=value#fragment'),
firstSignificantSubdomainRFC('http://user:password@example.com:8080/path?query=value#fragment');
Result:
┌─firstSignificantSubdomain('http://user:password@example.com:8080/path?query=value#fragment')─┬─firstSignificantSubdomainRFC('http://user:password@example.com:8080/path?query=value#fragment')─┐
│ │ example │
└──────────────────────────────────────────────────────────────────────────────────────────────┴─────────────────────────────────────────────────────────────────────────────────────────────────┘
cutToFirstSignificantSubdomain
Returns the part of the domain that includes top-level subdomains up to the “first significant subdomain”.
Syntax
cutToFirstSignificantSubdomain(url)
Arguments
url
— URL. String.
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain if possible, otherwise returns an empty string. String.
Example
Query:
SELECT
cutToFirstSignificantSubdomain('https://news.clickhouse.com.tr/'),
cutToFirstSignificantSubdomain('www.tr'),
cutToFirstSignificantSubdomain('tr');
Result:
┌─cutToFirstSignificantSubdomain('https://news.clickhouse.com.tr/')─┬─cutToFirstSignificantSubdomain('www.tr')─┬─cutToFirstSignificantSubdomain('tr')─┐
│ clickhouse.com.tr │ tr │ │
└───────────────────────────────────────────────────────────────────┴──────────────────────────────────────────┴──────────────────────────────────────┘
cutToFirstSignificantSubdomainRFC
Returns the part of the domain that includes top-level subdomains up to the “first significant subdomain”. It is similar to cutToFirstSignificantSubdomain but follows stricter rules to be compatible with RFC 3986 and is less performant.
Syntax
cutToFirstSignificantSubdomainRFC(url)
Arguments
url
— URL. String.
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain if possible, otherwise returns an empty string. String.
Example
Query:
SELECT
cutToFirstSignificantSubdomain('http://user:password@example.com:8080'),
cutToFirstSignificantSubdomainRFC('http://user:password@example.com:8080');
Result:
┌─cutToFirstSignificantSubdomain('http://user:password@example.com:8080')─┬─cutToFirstSignificantSubdomainRFC('http://user:password@example.com:8080')─┐
│ │ example.com │
└─────────────────────────────────────────────────────────────────────────┴────────────────────────────────────────────────────────────────────────────┘
cutToFirstSignificantSubdomainWithWWW
Returns the part of the domain that includes top-level subdomains up to the “first significant subdomain”, without stripping "www".
Syntax
cutToFirstSignificantSubdomainWithWWW(url)
Arguments
url
— URL. String.
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain (with "www") if possible, otherwise returns an empty string. String.
Example
Query:
SELECT
cutToFirstSignificantSubdomainWithWWW('https://news.clickhouse.com.tr/'),
cutToFirstSignificantSubdomainWithWWW('www.tr'),
cutToFirstSignificantSubdomainWithWWW('tr');
Result:
┌─cutToFirstSignificantSubdomainWithWWW('https://news.clickhouse.com.tr/')─┬─cutToFirstSignificantSubdomainWithWWW('www.tr')─┬─cutToFirstSignificantSubdomainWithWWW('tr')─┐
│ clickhouse.com.tr │ www.tr │ │
└──────────────────────────────────────────────────────────────────────────┴─────────────────────────────────────────────────┴─────────────────────────────────────────────┘
cutToFirstSignificantSubdomainWithWWWRFC
Returns the part of the domain that includes top-level subdomains up to the “first significant subdomain”, without stripping "www". Similar to cutToFirstSignificantSubdomainWithWWW but follows stricter rules to be compatible with RFC 3986 and is less performant.
Syntax
cutToFirstSignificantSubdomainWithWWW(url)
Arguments
url
— URL. String.
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain (with "www") if possible, otherwise returns an empty string. String.
Example
Query:
SELECT
cutToFirstSignificantSubdomainWithWWW('http:%2F%2Fwwwww.nova@mail.ru/economicheskiy'),
cutToFirstSignificantSubdomainWithWWWRFC('http:%2F%2Fwwwww.nova@mail.ru/economicheskiy');
Result:
┌─cutToFirstSignificantSubdomainWithWWW('http:%2F%2Fwwwww.nova@mail.ru/economicheskiy')─┬─cutToFirstSignificantSubdomainWithWWWRFC('http:%2F%2Fwwwww.nova@mail.ru/economicheskiy')─┐
│ │ mail.ru │
└───────────────────────────────────────────────────────────────────────────────────────┴──────────────────────────────────────────────────────────────────────────────────────────┘
cutToFirstSignificantSubdomainCustom
Returns the part of the domain that includes top-level subdomains up to the first significant subdomain. Accepts custom TLD list name.
This can be useful if you need a fresh TLD list or if you have a custom list.
Configuration example
<!-- <top_level_domains_path>/var/lib/clickhouse/top_level_domains/</top_level_domains_path> -->
<top_level_domains_lists>
<!-- https://publicsuffix.org/list/public_suffix_list.dat -->
<public_suffix_list>public_suffix_list.dat</public_suffix_list>
<!-- NOTE: path is under top_level_domains_path -->
</top_level_domains_lists>
Syntax
cutToFirstSignificantSubdomain(url, tld)
Arguments
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain. String.
Example
Query:
SELECT cutToFirstSignificantSubdomainCustom('bar.foo.there-is-no-such-domain', 'public_suffix_list');
Result:
┌─cutToFirstSignificantSubdomainCustom('bar.foo.there-is-no-such-domain', 'public_suffix_list')─┐
│ foo.there-is-no-such-domain │
└───────────────────────────────────────────────────────────────────────────────────────────────┘
See Also
cutToFirstSignificantSubdomainCustomRFC
Returns the part of the domain that includes top-level subdomains up to the first significant subdomain. Accepts custom TLD list name. It is similar to cutToFirstSignificantSubdomainCustom but follows stricter rules according to RFC 3986 and is generally less performant as a result.
Syntax
cutToFirstSignificantSubdomainRFC(url, tld)
Arguments
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain. String.
See Also
cutToFirstSignificantSubdomainCustomWithWWW
Returns the part of the domain that includes top-level subdomains up to the first significant subdomain without stripping www
. Accepts custom TLD list name.
It can be useful if you need a fresh TLD list or if you have a custom list.
Configuration example
<!-- <top_level_domains_path>/var/lib/clickhouse/top_level_domains/</top_level_domains_path> -->
<top_level_domains_lists>
<!-- https://publicsuffix.org/list/public_suffix_list.dat -->
<public_suffix_list>public_suffix_list.dat</public_suffix_list>
<!-- NOTE: path is under top_level_domains_path -->
</top_level_domains_lists>
Syntax
cutToFirstSignificantSubdomainCustomWithWWW(url, tld)
Arguments
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain without stripping
www
.
Type: String.
Example
Query:
SELECT cutToFirstSignificantSubdomainCustomWithWWW('www.foo', 'public_suffix_list');
Result:
┌─cutToFirstSignificantSubdomainCustomWithWWW('www.foo', 'public_suffix_list')─┐
│ www.foo │
└──────────────────────────────────────────────────────────────────────────────┘
See Also
cutToFirstSignificantSubdomainCustomWithWWWRFC
Returns the part of the domain that includes top-level subdomains up to the first significant subdomain without stripping www
. Accepts custom TLD list name. It is similar to cutToFirstSignificantSubdomainCustomWithWWW but follows stricter rules according to RFC 3986 and is generally less performant as a result.
Syntax
cutToFirstSignificantSubdomainCustomWithWWWRFC(url, tld)
Arguments
Returned value
- Part of the domain that includes top-level subdomains up to the first significant subdomain without stripping
www
. String.
See Also
firstSignificantSubdomainCustom
Returns the first significant subdomain. Accepts customs TLD list name.
Can be useful if you need fresh TLD list or you have custom.
Configuration example:
<!-- <top_level_domains_path>/var/lib/clickhouse/top_level_domains/</top_level_domains_path> -->
<top_level_domains_lists>
<!-- https://publicsuffix.org/list/public_suffix_list.dat -->
<public_suffix_list>public_suffix_list.dat</public_suffix_list>
<!-- NOTE: path is under top_level_domains_path -->
</top_level_domains_lists>
Syntax
firstSignificantSubdomainCustom(url, tld)
Arguments
Returned value
- First significant subdomain.
Type: String.
Example
Query:
SELECT firstSignificantSubdomainCustom('bar.foo.there-is-no-such-domain', 'public_suffix_list');
Result:
┌─firstSignificantSubdomainCustom('bar.foo.there-is-no-such-domain', 'public_suffix_list')─┐
│ foo │
└──────────────────────────────────────────────────────────────────────────────────────────┘
See Also
firstSignificantSubdomainCustomRFC
Returns the first significant subdomain. Accepts customs TLD list name. Similar to firstSignificantSubdomainCustom but follows stricter rules according to RFC 3986 and is generally less performant as a result.
Syntax
firstSignificantSubdomainCustomRFC(url, tld)
Arguments
Returned value
- First significant subdomain.
Type: String.
See Also
port
Returns the port or default_port
if there is no port in the url
(or in case of validation error).
Syntax
port(url [, default_port = 0])
Arguments
Returned value
- Port or the default port if there is no port in the URL or in case of a validation error. UInt16.
Example
Query:
SELECT port('http://paul@www.example.com:80/');
Result:
┌─port('http://paul@www.example.com:80/')─┐
│ 80 │
└─────────────────────────────────────────┘
portRFC
Returns the port or default_port
if there is no port in the url
(or in case of validation error). Similar to port, but RFC 3986 conformant.
Syntax
portRFC(url [, default_port = 0])
Arguments
Returned value
- Port or the default port if there is no port in the URL or in case of a validation error. UInt16.
Example
Query:
SELECT
port('http://user:password@example.com:8080'),
portRFC('http://user:password@example.com:8080');
Result:
┌─port('http://user:password@example.com:8080')─┬─portRFC('http://user:password@example.com:8080')─┐
│ 0 │ 8080 │
└───────────────────────────────────────────────┴──────────────────────────────────────────────────┘
path
Returns the path. Example: /top/news.html
The path does not include the query string.
pathFull
The same as above, but including query string and fragment. Example: /top/news.html?page=2#comments
queryString
Returns the query string. Example: page=1&lr=213. query-string does not include the initial question mark, as well as # and everything after #.
fragment
Returns the fragment identifier. fragment does not include the initial hash symbol.
queryStringAndFragment
Returns the query string and fragment identifier. Example: page=1#29390.
extractURLParameter(url, name)
Returns the value of the ‘name’ parameter in the URL, if present. Otherwise, an empty string. If there are many parameters with this name, it returns the first occurrence. This function works under the assumption that the parameter name is encoded in the URL exactly the same way as in the passed argument.
extractURLParameters(url)
Returns an array of name=value strings corresponding to the URL parameters. The values are not decoded in any way.
extractURLParameterNames(url)
Returns an array of name strings corresponding to the names of URL parameters. The values are not decoded in any way.
URLHierarchy(url)
Returns an array containing the URL, truncated at the end by the symbols /,? in the path and query-string. Consecutive separator characters are counted as one. The cut is made in the position after all the consecutive separator characters.
URLPathHierarchy(url)
The same as above, but without the protocol and host in the result. The / element (root) is not included.
URLPathHierarchy('https://example.com/browse/CONV-6788') =
[
'/browse/',
'/browse/CONV-6788'
]
encodeURLComponent(url)
Returns the encoded URL. Example:
SELECT encodeURLComponent('http://127.0.0.1:8123/?query=SELECT 1;') AS EncodedURL;
┌─EncodedURL───────────────────────────────────────────────┐
│ http%3A%2F%2F127.0.0.1%3A8123%2F%3Fquery%3DSELECT%201%3B │
└──────────────────────────────────────────────────────────┘
decodeURLComponent(url)
Returns the decoded URL. Example:
SELECT decodeURLComponent('http://127.0.0.1:8123/?query=SELECT%201%3B') AS DecodedURL;
┌─DecodedURL─────────────────────────────┐
│ http://127.0.0.1:8123/?query=SELECT 1; │
└────────────────────────────────────────┘
encodeURLFormComponent(url)
Returns the encoded URL. Follows rfc-1866, space(
) is encoded as plus(+
).
Example:
SELECT encodeURLFormComponent('http://127.0.0.1:8123/?query=SELECT 1 2+3') AS EncodedURL;
┌─EncodedURL────────────────────────────────────────────────┐
│ http%3A%2F%2F127.0.0.1%3A8123%2F%3Fquery%3DSELECT+1+2%2B3 │
└───────────────────────────────────────────────────────────┘
decodeURLFormComponent(url)
Returns the decoded URL. Follows rfc-1866, plain plus(+
) is decoded as space(
).
Example:
SELECT decodeURLFormComponent('http://127.0.0.1:8123/?query=SELECT%201+2%2B3') AS DecodedURL;
┌─DecodedURL────────────────────────────────┐
│ http://127.0.0.1:8123/?query=SELECT 1 2+3 │
└───────────────────────────────────────────┘
netloc
Extracts network locality (username:password@host:port
) from a URL.
Syntax
netloc(url)
Arguments
url
— URL. String.
Returned value
username:password@host:port
.
Type: String
.
Example
Query:
SELECT netloc('http://paul@www.example.com:80/');
Result:
┌─netloc('http://paul@www.example.com:80/')─┐
│ paul@www.example.com:80 │
└───────────────────────────────────────────┘
Functions that Remove Part of a URL
If the URL does not have anything similar, the URL remains unchanged.
cutWWW
Removes no more than one ‘www.’ from the beginning of the URL’s domain, if present.
cutQueryString
Removes query string. The question mark is also removed.
cutFragment
Removes the fragment identifier. The number sign is also removed.
cutQueryStringAndFragment
Removes the query string and fragment identifier. The question mark and number sign are also removed.
cutURLParameter(url, name)
Removes the name
parameter from URL, if present. This function does not encode or decode characters in parameter names, e.g. Client ID
and Client%20ID
are treated as different parameter names.
Syntax
cutURLParameter(url, name)
Arguments
Returned value
- url with
name
URL parameter removed.
Type: String
.
Example
Query:
SELECT
cutURLParameter('http://bigmir.net/?a=b&c=d&e=f#g', 'a') as url_without_a,
cutURLParameter('http://bigmir.net/?a=b&c=d&e=f#g', ['c', 'e']) as url_without_c_and_e;
Result:
┌─url_without_a────────────────┬─url_without_c_and_e──────┐
│ http://bigmir.net/?c=d&e=f#g │ http://bigmir.net/?a=b#g │
└──────────────────────────────┴──────────────────────────┘