basics.md

SQLY Basics

📖 Introduction

SQLY (Standard Query Language) is a YAML-based query language designed for structured and semi-structured data. It is inspired by JQL, Kusto, and DQL while offering a human-readable syntax.

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🛠 Basic Query Structure

A simple SQLY query consists of the following components:

• select: Specifies the fields to retrieve.
• from: Defines the data source.
• where: Filters the results.
• order_by: Sorts the results.
• limit: Limits the number of returned rows.

✅ Example 1: Fetch Active Users

query:
  select: [id, name, email]
  from: users
  where:
    status: active
  order_by: name ASC
  limit: 50

✅ Example 2: Fetch Orders Above a Certain Price

query:
  select: [order_id, customer, total_price]
  from: orders
  where:
    total_price:
      gt: 100
  order_by: total_price DESC

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🔍 Filtering & Logical Operators

SQLY supports multiple conditions using logical operators:

Operator	Description
gt	Greater than
lt	Less than
gte	Greater than or equal
lte	Less than or equal
in	Matches any value in a list
not	Negates a condition

✅ Example 3: Fetch High-Value Orders from Specific Customers

query:
  select: [order_id, customer, total_price]
  from: orders
  where:
    total_price:
      gte: 500
    customer:
      in: ["Alice", "Bob", "Charlie"]

✅ Example 4: Fetch Users Who Are Not Admins

query:
  select: [id, name]
  from: users
  where:
    role:
      not: admin

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📊 Aggregation & Grouping

SQLY allows aggregation functions with group_by.

✅ Example 5: Calculate Average Order Value per Customer

query:
  select:
    - customer_id
    - avg: total_price
  from: orders
  group_by: customer_id

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📌 Summary

• Use select to define fields.
• from specifies the data source.
• where applies filtering.
• Use order_by for sorting results.
• Apply group_by for aggregations.

Proceed to Advanced Features to explore more capabilities.