PCRE2 regexes are used in various options in MaxScale. I think the documentation for some of these options could be clarified.

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Configuration

—

The MaxScale configuration section has a short summary of regex support here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

This documentation could use some improvements:

• I think this section should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this section should mention that some of MaxScale's features support PCRE2's options, which can change how patterns are interpreted. As part of this, I think this section should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

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Filters

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Binlog Filter

The Binlog Filter uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-binlog-filter/#match

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should have an example of a pattern.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The exclude option

https://mariadb.com/kb/en/mariadb-maxscale-23-binlog-filter/#exclude

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should have an example of a pattern.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Consistent Critical Read Filter

The Consistent Critical Read Filter uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-consistent-critical-read-filter/#match

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The ignore option

https://mariadb.com/kb/en/mariadb-maxscale-23-consistent-critical-read-filter/#ignore

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-consistent-critical-read-filter/#filter-options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Database Firewall Filter

The Database Firewall Filter uses PCRE2 regexes for the following:

The regex option

https://mariadb.com/kb/en/mariadb-maxscale-23-database-firewall-filter/#regex

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Named Server Filter

The Named Server Filter uses PCRE2 regexes for the following:

The matchXY option

https://mariadb.com/kb/en/mariadb-maxscale-23-named-server-filter/#matchxy

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should have an example of a pattern.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-named-server-filter/#filter-options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Query Log All Filter

The Query Log All Filter uses PCRE2 regexes for the following:

The match and exclude options

https://mariadb.com/kb/en/mariadb-maxscale-23-query-log-all-filter/#match-and-exclude

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-query-log-all-filter/#filter-options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Regex Filter

The Regex Filter uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-regex-filter/#match

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The replace option

https://mariadb.com/kb/en/mariadb-maxscale-23-regex-filter/#replace

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2's regex syntax for replacement patterns.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-regex-filter/#filter-options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Tee Filter

The Tee Filter uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-tee-filter/#match

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The exclude option

https://mariadb.com/kb/en/mariadb-maxscale-23-tee-filter/#exclude

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-tee-filter/#options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Top Filter

The Top Filter uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-top-filter/#match

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The exclude option

https://mariadb.com/kb/en/mariadb-maxscale-23-top-filter/#exclude

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention that the options option affects how the pattern is compiled.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

The options option

https://mariadb.com/kb/en/mariadb-maxscale-23-top-filter/#filter-options

This one is not a pattern, but it does control how patterns are interpreted.

This documentation could use some improvements:

• I think this description should link to PCRE2's API documentation section on "compiling a pattern" that describes what each option means:

https://www.pcre.org/current/doc/html/pcre2api.html#SEC20

• I think this description should mention which PCRE2 options are used if the options option is not set. (The answer seems to be "no options are used by default".)

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

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Routers

—

Avro Router

The Avro Router uses PCRE2 regexes for the following:

The match option

https://mariadb.com/kb/en/mariadb-maxscale-23-avrorouter/#match

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should have an example of a pattern.

The exclude option

https://mariadb.com/kb/en/mariadb-maxscale-23-avrorouter/#exclude

This documentation could use some improvements:

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should have an example of a pattern.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions

—

Schema Router

The Schema Router uses PCRE2 regexes for the following:

The ignore_databases_regex option

https://mariadb.com/kb/en/mariadb-maxscale-23-schemarouter-router/#ignore_databases_regex

This documentation could use some improvements:

• I think this description should mention that it uses PCRE2 regexes.

• I think this description should link to PCRE2's syntax and pattern documentation pages:

https://www.pcre.org/current/doc/html/pcre2syntax.html

https://www.pcre.org/current/doc/html/pcre2pattern.html

• I think this description should mention which PCRE2 options are used. (The answer seems to be "no options are used for this option".)

• I think this description should have an example of a pattern.

• I think this description should link here:

https://mariadb.com/kb/en/mariadb-maxscale-23-mariadb-maxscale-configuration-usage-scenarios/#regular-expressions