There was a need to work with the MS SQL database, but I did not want to install and understand the complex SQL Management Studio program, and this product turned out to be very easy to install and use. For more then 2 month i've used the tool haven't came across any issues.
DBeaver - DBeaver - Universal Database Manager and SQL Client.
draw.io - Online diagramming application
DataGrip - Tool for SQL and databases
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
MySQL Workbench - MySQL Workbench is a unified visual tool for database architects, developers, and DBAs.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.