mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-19 14:11:58 +00:00
8623cb232c
* CLICKHOUSE-4063: less manual html @ index.md * CLICKHOUSE-4063: recommend markdown="1" in README.md * CLICKHOUSE-4003: manually purge custom.css for now * CLICKHOUSE-4064: expand <details> before any print (including to pdf) * CLICKHOUSE-3927: rearrange interfaces/formats.md a bit * CLICKHOUSE-3306: add few http headers * Remove copy-paste introduced in #3392 * Hopefully better chinese fonts #3392 * get rid of tabs @ custom.css * Apply comments and patch from #3384 * Add jdbc.md to ToC and some translation, though it still looks badly incomplete * minor punctuation * Add some backlinks to official website from mirrors that just blindly take markdown sources * Do not make fonts extra light * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's//g' {} * find . -name '*.md' -type f | xargs -I{} perl -pi -e 's/ sql/g' {} * Remove outdated stuff from roadmap.md * Not so light font on front page too * Refactor Chinese formats.md to match recent changes in other languages
34 lines
1.1 KiB
Markdown
34 lines
1.1 KiB
Markdown
# Comparison functions
|
|
|
|
Comparison functions always return 0 or 1 (Uint8).
|
|
|
|
The following types can be compared:
|
|
|
|
- numbers
|
|
- strings and fixed strings
|
|
- dates
|
|
- dates with times
|
|
|
|
within each group, but not between different groups.
|
|
|
|
For example, you can't compare a date with a string. You have to use a function to convert the string to a date, or vice versa.
|
|
|
|
Strings are compared by bytes. A shorter string is smaller than all strings that start with it and that contain at least one more character.
|
|
|
|
Note. Up until version 1.1.54134, signed and unsigned numbers were compared the same way as in C++. In other words, you could get an incorrect result in cases like SELECT 9223372036854775807 > -1. This behavior changed in version 1.1.54134 and is now mathematically correct.
|
|
|
|
## equals, a = b and a == b operator
|
|
|
|
## notEquals, a ! operator= b and a `<>` b
|
|
|
|
## less, `< operator`
|
|
|
|
## greater, `> operator`
|
|
|
|
## lessOrEquals, `<= operator`
|
|
|
|
## greaterOrEquals, `>= operator`
|
|
|
|
|
|
[Original article](https://clickhouse.yandex/docs/en/query_language/functions/comparison_functions/) <!--hide-->
|