Databases and SQL

Almost all the software we build at TintoDev ends up in a database, and almost every performance problem we get called in to fix starts there: a poorly thought-out model, a missing index or a query that pulls far more data than it needs. That is why this category puts more weight on SQL and data modelling than on any specific engine. What you learn in PostgreSQL carries over almost entirely to MySQL or SQL Server; what switching engines will not fix is the habit of designing tables without thinking about how they will be queried. We include MongoDB because it has its place, though not as an automatic replacement for a relational database. We pick courses that work with realistic data and explain execution plans, not just syntax. There is a good range in Spanish to get started; for advanced tuning, the reference courses are usually in English.

Who it is for

• People starting out in programming or analysis who need to query data without relying on someone else.
• Developers who use an ORM and have never looked at the SQL it generates underneath.
• Analysts who export everything to Excel today and want to do the work directly in the database.
• Teams with an application that has slowed down and who suspect the database.

What you will learn

• SQL from scratch: SELECT, filters, JOINs, grouping and subqueries, until you read them fluently.
• Relational modelling and normalisation, and when it makes sense to break those rules.
• Indexes and execution plans, to understand why a query takes as long as it does.
• Transactions and concurrency, the part that fails when many users write at the same time.
• Practical differences between PostgreSQL, MySQL and SQL Server.
• MongoDB and the document model, with its advantages and its costs.

Recommended order

1. Standard SQL on any engine. PostgreSQL is a good choice because it is free and sticks closely to the standard.
2. Data modelling with a case of your own: design the tables for something you know well before moving on.
3. Performance: indexes, execution plans and transactions.
4. One specific engine in depth (whichever your company uses) and MongoDB if a project calls for it.

Backend Bootcamp 2026: Python, Flask, REST API, Docker, SQL

This English-language course teaches backend development with Python and PostgreSQL by building REST APIs in Flask, with security and monitoring included from early on. We would recommend it to people who already code a little and want to see how a complete backend fits together, because the published syllabus goes past basic CRUD into data modeling, JWT, bcrypt, HTTPS, concurrency and Grafana metrics.

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Master en SQL Server: Desde Cero hasta Experto [2026]

This is a broad, Spanish-language SQL Server course for people who need to work with Microsoft's full database platform, not just write queries. We would point to it for anyone who will build or administer databases at companies already on SQL Server, because the published syllabus runs from basic T-SQL to security, backups, performance tuning and SSIS integration.

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SQL desde Cero: Conviértete en Analista de Datos en 2026

This is a Spanish-language SQL course for people who want to break into data analysis and need practical queries for the job rather than database theory. We would recommend it because the published syllabus combines querying, some statistics done directly in SQL, a portfolio case study and interview prep, which is what a first analyst role actually asks for.

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Frequently asked questions

Which database should I learn first?

PostgreSQL, unless your job already uses another one. It is free, follows the SQL standard closely and what you learn on it transfers almost unchanged to MySQL or SQL Server. If your company runs SQL Server, start there and skip the translation step.

How long does it take to learn SQL?

Basic queries take a few weeks of steady practice. Writing complex queries comfortably and understanding their performance takes months, and depends mostly on how much you practise with real data.

SQL or MongoDB?

SQL first, because most business systems run on relational databases and relational modelling shapes how you think about data. MongoDB fits when the structure varies a lot between records or when documents are read as a whole. At TintoDev we use it for specific cases, not as the default.

Do I need to know how to code to learn SQL?

No. SQL is a query language you can learn on its own, and many analysts use it daily without coding in any other language. Programming helps when you want to embed queries in an application, but it is not a prerequisite.

Are there SQL courses in Spanish?

Yes, there is a wide range in Spanish, especially for SQL from scratch, MySQL and SQL Server. The catalogue mixes Spanish and English courses, and each listing shows the language of the course. For advanced tuning and administration, the reference courses are usually in English.