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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: ...

Vim Plugin Manager Installation Download it from its GitHub repository or the risky but easy way using curl: curl -fLo ~/.vim/autoload/plug.vim --create-dirs https://raw.githubusercontent.com/junegunn/vim-plug/master/plug.vim Adding Plugins Add a plugin section to the .vimrc: .vimrc call plug#begin() " The default plugin directory will be as follows: " - Vim (Linux/macOS): '~/.vim/plugged' " - Vim (Windows): '~/vimfiles/plugged' " - Neovim (Linux/macOS/Windows): stdpath('data') . '/plugged' " You can specify a custom plugin directory by passing it as the argument " - e.g. `call plug#begin('~/.vim/plugged')` " - Avoid using standard Vim directory names like 'plugin' " Make sure you use single quotes " Gruvbox Theme Plug 'sainnhe/gruvbox-material' " Initialize plugin system " - Automatically executes `filetype plugin indent on` and `syntax enable`. call plug#end() " You can revert the settings after the call like so: " filetype indent off " Disable file-type-specific indentation " syntax off " Disable syntax highlighting ...

Autostart Verzeichnis aufrufen Run from the command line (⊞+R) shell:startup List Processes on the Command Line tasklist | more Find by name tasklist /FI "IMAGENAME eq notepad.exe" Abbildname PID Sitzungsname Sitz.-Nr. Speichernutzung ========================= ======== ================ =========== =============== notepad.exe 23496 Console 3 14.516 K Kill Processes by PID or Name on the Command Line Kill by PID taskkill /F /PID PID_NUMBER Kill by Name taskkill /IM "notepad.exe" /F Find Process by Port used E.g. finding processes using port 9000. ...

Ignore Namespaces in XPath Query e.g. Query for all xxx nodes ignoring their namespace: xmllint --xpath '//*[local-name()="xxx"]' input.xml An example parsing URLs from a sitemap XML. The URLs are located in //url/loc where all nodes are bound to the namespace http://www.sitemaps.org/schemas/sitemap/0.9. The following query ignores the namespace xmllint --xpath '//*[local-name()="url"]/*[local-name()="loc"]' sitemap.xml Pretty Print XML in the Console using xmllint echo '<blogs><blog url="https://www.hascode.com/">hasCode.com</blog></blogs>' | xmllint --format - <?xml version="1.0"?> <blogs> <blog url="https://www.hascode.com/">hasCode.com</blog> </blogs> ...