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Use List of Parameters in Annotation-based Query Possible using MyBatis Dynamic SQL feature package com.hascode.example.mybatis; import org.apache.ibatis.annotations.Mapper; import org.apache.ibatis.annotations.Param; import org.apache.ibatis.annotations.Select; import java.util.List; @Mapper public interface SampleMapper { @Select({"<script>", "SELECT sample.bar", "FROM sampletable sample", "WHERE sample.id IN", "<foreach item='item' index='index' collection='ids'", "open='(' separator=',' close=')'>", "#{item}", "</foreach>", "</script>"}) List<Foo> getSamplesMatchingIds(@Param("ids") List<String> ids); } The mapper may now be used with a list of parameter objects: var samples = sampleMapper.getSamplesMatchingIds(List.of("24059e5b-aa07-424d-855e-50f499b8f697", "65140fc0-fc9f-42d2-9531-5e5d6caeba30")); Call a Procedure package com.hascode.example.mybatis; import org.apache.ibatis.annotations.Mapper; import org.apache.ibatis.annotations.Options; import org.apache.ibatis.annotations.Select; import org.apache.ibatis.mapping.StatementType; @Mapper public interface SampleMapper { @Select("CALL SCHEMA.CL.setScope(#{scope})") @Options(statementType = StatementType.CALLABLE) void setScope(int scope); } ...

Aggregate existing Labels MATCH (n) RETURN DISTINCT labels(n) Or unwinding label pairs MATCH (n) WITH DISTINCT labels(n) AS labels UNWIND labels AS label RETURN DISTINCT label ORDER BY label

The USE Methodology USE stands for Utilization, Saturation, and Errors. Developed by Brendan Gregg, it’s a low-level diagnostic tool for infrastructure and system resources. Utilization – How much of a resource is used? (e.g., 70% CPU) Saturation – Is the system over capacity? (e.g., CPU run queue) Errors – Are there hardware or system faults? (e.g., disk errors) Best for: Bottleneck analysis on servers, network, disk, memory Source: https://grafana.com/docs/grafana/latest/dashboards/build-dashboards/best-practices/ The RED Methodology RED focuses on service-level performance and is tailored for microservices and HTTP-based systems. ...

WordPress anonymize IP in comments Add as last line in theme’s functions.php: function wpb_remove_commentsip($comment_author_ip) { return '127.0.0.1'; } add_filter('pre_comment_user_ip','wpb_remove_commentsip'); WordPress remove version info Add as last line in theme’s functions.php: function remove_version_info() { return ''; } add_filter('the_generator', 'remove_version_info'); List of all WordPress Hooks

Get size of a table SELECT pg_size_pretty(pg_total_relation_size('schemaname.tablename')); Select unique combination of fields / tuples SELECT DISTINCT ON(field1, field2) field1, field2 FROM thetable Select rows where a combination of fields is not unique SELECT columnA, columnB, count(*) AS count FROM thetable GROUP BY columnA, columnB HAVING count(*) > 1 Search for rows with array containing value Assuming, the field appointments has the type date[] SELECT * FROM mtable WHERE appointments @> ARRAY['2023-09-19'::date] ...

Virtual Environments Create and activate a venv python -m venv /path/to/new-env (1) source /path/to/new-env/bin/activate (2) 1 Creates a new virtual environment 2 Activate the new virtual environment Deactivate venv deactivate Save used dependencies to a file pip freeze > dependencies.txt Install dependencies from file pip install -r dependencies.txt Storing and fetching Credentials from the System Keyring I am using jaraco/keyring here: pip install keyring import keyring keyring.set_password("system", "db.sample.password", "xoxo") print(keyring.get_password("system", "db.sample.password")) ...

Installation Installing rustup first…​ install rustup via shell script curl --proto '=https' --tlsv1.2 https://sh.rustup.rs -sSf | sh install rustup via brew brew install rustup-init (1) rustup-init (2) Welcome to Rust! [...] Current installation options: default host triple: aarch64-apple-darwin default toolchain: stable (default) profile: default modify PATH variable: yes 1) Proceed with standard installation (default - just press enter) 2) Customize installation 3) Cancel installation 1 install rustup 2 install rust binaries and add them to paths etc…​ ...

SBT – Eclipse Plugin Add to your ~/.sbt/plugins/plugins.sbt addSbtPlugin("com.typesafe.sbteclipse" % "sbteclipse-plugin" % "2.1.1")

Define and Configure Log Groups This allows to configure a group of loggers at the same time Define a log group named myaspect with two packages application.properties logging.group.myaspect=com.hascode.package1,com.hascode.package2 Configure the log group and set all loggers to level TRACE application.properties logging.level.myaspect=TRACE This is also possible as parameter on startup java -Dlogging.level.myaspect=TRACE myapp.jar Use JUnit 5 with Spring Boot Use newer versions of Surefire and Failsafe plugins: <properties> [..] <maven-failsafe-plugin.version>2.22.0</maven-failsafe-plugin.version> <maven-surefire-plugin.version>2.22.0</maven-surefire-plugin.version> </properties> ...

Count unique / all values SELECT COUNT(DISTINCT <FIELDNAME>), COUNT(ALL <FIELDNAME>) FROM <TABLE>; Partially anonymize e-mail addresses UPDATE <TABLE_NAME> SET <EMAIL_FIELD>= INSERT( <EMAIL_FIELD>, POSITION('@' IN <EMAIL_FIELD>), 100, CONCAT(FLOOR(1 + (RAND() * 100)),'@hascode.com')) WHERE POSITION('@' IN <EMAIL_FIELD>)>0; Find duplicate entries SELECT COUNT(*), <FIELDNAME> FROM <TABLENAME> GROUP BY <FIELDNAME> HAVING COUNT(*)>1; MySQL Fix Zero Dates for Data Imports Error: ERROR 1067 (42000) at line 1234: Invalid default value for ‘datefield’ In newer MySQL Versions zero in date or zero dates are forbidden .. check this with: ...