RLIKE
The RLIKE operator allows you to check if a string matches a specified regular expression pattern.
Returns true if str matches regexp, or false
otherwise.
Syntax
rlike(str, regexp)
Arguments
- str
-
A string expression
- regexp
-
A string expression. The regex string should be a Java regular expression.
String literals (including regex patterns) are unescaped in our SQL parser. For example, to match "\abc", a regular expression for regexp can be "^\abc$".
Examples
The following example sets the value of the
spark.sql.parser.escapedStringLiterals configuration parameter to
true. This parameter is specific to the Spark SQL engine. The
spark.sql.parser.escapedStringLiterals parameter in Spark SQL controls how the SQL
parser handles escaped string literals. When set to true, the parser will interpret
backslash characters (\) within string literals as escape characters, allowing you
to include special characters like newlines, tabs, and quotation marks within your string
values.
SET spark.sql.parser.escapedStringLiterals=true; spark.sql.parser.escapedStringLiterals true
For example, with spark.sql.parser.escapedStringLiterals=true, you could use
the following string literal in your SQL query:
SELECT 'Hello, world!\n'
The newline character \n would be interpreted as a literal newline character
in the output.
The following example performs a regular expression pattern match. The first argument is
passed to the RLIKE operator. It's a string that represents a file path, where the actual
username is replaced with the pattern '****'. The second argument is the regular expression
pattern used for the matching. The output (true) indicates that the first string
('%SystemDrive%\Users\****') matches the regular expression pattern
('%SystemDrive%\\Users.*').
SELECT rlike('%SystemDrive%\Users\John', '%SystemDrive%\Users.*'); true
