freecodecamp

 freecodecamp

freecodecamp


1- SQL Join Types – Inner Join Vs Outer Join

2- Meta Tag in HTML – What is Metadata and Meta Description Example

3- Learn Programming – Free Software Development Courses for Beginners

4- How to Use Google – Search Tips for Better Results








Comments

Post a Comment

Popular posts from this blog

What is a DBAPI ?

Image
 DB-API DB-API definition: - We will sometimes want to interact with our database and use its results in a specific programming language.   - To build web applications or data pipelines in a specific language like (Ruby, Python, Javascript, etc.). - That's where DBAPIs come in. A DB-API:  - A DB-API provides a standard for one programming language (like python) to talk to a relational database server. - Is a low-level library for writing SQL statements that connect to a database.  - Also known as database adapters. - Different DBAPIs exist for every server framework or language + database system. - Database adapters define a standard for using a database (with SQL) and using the results of database queries as input data in the given language. -- Turn a selected (SELECT * from some_table;) list of rows into an array of objects in Javascript for say a NodeJS adapter; or a list of tuples in Python for a Python adapter. Examples across languages and server frameworks: - For Ruby (e.g.
Read more

What Is Relational Databases

Image
What Is Relational Databases  Definitions : -   A database is a collection of data. -    A database system is a system for storing collections of data in some organized way. -    It uses a structure that allows us to identify and access data  in relation  to another piece of data in the database. -    Often, data in a relational database is organized into tables. What is a Relational Database Management System (RDBMS)? -    A relational database management system (RDBMS) is a program that allows you to create, update, and administer a relational database. -   Most relational database management systems use the SQL language to access the database. What is SQL? - SQL ( S tructured  Q uery  L anguage) is a programming language used to communicate with data stored in a relational database management system. - Every relational database system (PostgreSQL, SQLite, MySQL, etc) has its own "flavor" of SQL it implements. - Because they are not 100% compliant with SQL standa
Read more

SQLAlchemy Model.query cheat-sheet

Image
SQLAlchemy  Model  query-cheat-sheet Query Methods Here are some useful query methods to get to know.  - Select records all() MyModel.query.all() Fetches all records from a table. Returns list of objects. first() MyModel.query.first() Fetches just the first result. Returns object or None. - Filtering filter_by() MyModel.query.filter_by(attr='some value') Similar to SELECT * from ... WHERE filter() Examples: MyModel.query.filter(MyOtherModel.some_attr='some value') OrderItem.query.filter(Product.id=3) Similar to filter_by , but instead, you specify attributes on a given Model.-- -- equals: query.filter(User.name == 'ed') -- not equals: query.filter(User.name != 'ed') LIKE : query.filter(User.name.like('%ed%')) ILIKE (case-insensitive LIKE): query.filter(User.name.ilike('%ed%')) IN: query.filter(User.name.in_(['ed', 'wendy', 'jack'])) NOT IN: query.filter(~User.name.in_(['ed', 'wendy', 'jack'
Read more