SkillCoded

CATEGORY

Databases and Data

Relational data, SQL, PostgreSQL, and practical data handling.

LESSONS

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Beginner

Relational Data, Tables, Rows, and Keys

SQL Fundamentals

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Beginner

Install a Local SQL Practice Database

SQL Fundamentals

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Beginner

Create Tables and Choose Column Types

SQL Fundamentals

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Beginner

Select Columns and Rows

SQL Fundamentals

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Beginner

Filter Rows with WHERE

SQL Fundamentals

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Beginner

Sort, Limit, and Remove Duplicates

SQL Fundamentals

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Beginner

Work with NULL and Unknown Values

SQL Fundamentals

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Beginner

Insert Rows Safely

SQL Fundamentals

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Beginner

Update Rows with Targeted Conditions

SQL Fundamentals

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Beginner

Delete Rows and Protect Scope

SQL Fundamentals

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Beginner

Expressions, Aliases, and String Operations

SQL Fundamentals

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Beginner

Aggregate Functions

SQL Fundamentals

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Beginner

Group Results with GROUP BY and HAVING

SQL Fundamentals

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Beginner

Join Tables with INNER JOIN

SQL Fundamentals

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Beginner

Keep Unmatched Rows with OUTER JOIN

SQL Fundamentals

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Intermediate

Subqueries and Common Table Expressions

SQL Fundamentals

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Intermediate

Constraints and Data Integrity

SQL Fundamentals

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Intermediate

SQL Fundamentals Capstone

SQL Fundamentals

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Intermediate

PostgreSQL Architecture and Client Connections

PostgreSQL

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Intermediate

Databases, Schemas, and Search Path

PostgreSQL

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Intermediate

PostgreSQL Data Types and Type Casting

PostgreSQL

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Intermediate

Identity Columns and Sequences

PostgreSQL

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Intermediate

Transactions, Commit, Rollback, and Savepoints

PostgreSQL

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Intermediate

MVCC and Transaction Visibility

PostgreSQL

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Intermediate

Transaction Isolation and Concurrency

PostgreSQL

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Intermediate

Index Fundamentals and B-tree Indexes

PostgreSQL

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Intermediate

Read EXPLAIN Query Plans

PostgreSQL

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Intermediate

Views and Materialized Views

PostgreSQL

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Intermediate

Roles, Privileges, and Ownership

PostgreSQL

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Intermediate

Backup and Restore with pg_dump

PostgreSQL

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Intermediate

VACUUM, ANALYZE, and Table Maintenance

PostgreSQL

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Intermediate

Locks, Blocking, and Deadlock Investigation

PostgreSQL

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Intermediate

JSONB and Structured Documents

PostgreSQL

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Intermediate

PostgreSQL Operations Capstone

PostgreSQL

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