Maybe not, but I used to build a lot of powerful, blazing-fast Transact-SQL stored procedures that contained a large percentage of a small investment management firm's business logic. It kept them committed to SQL Server, true, but it wasn't like they would have benefitted from switching to Oracle or MySQL, anyway.
Most developers use about 5% of Transact-SQL's capabilities.
For sure SQL is influential and in widespread use, but it’s not really a programming language. Although you can find its query language embedded in a lot of other programming code, for sure. I’m glad to know it; just being contrarian, really.