Text & dates in SQLite
LOWER and UPPER change text case; LENGTH counts characters. SQLite stores date-like values as text, real or integer formats, not a dedicated date type. ISO YYYY-MM-DD text sorts by calendar date. Functions differ across SQL dialects.
हिन्दी में समझें
LOWER/UPPER अक्षर केस, LENGTH लंबाई देता है। SQLite का अलग date प्रकार नहीं है। YYYY-MM-DD टेक्स्ट कैलेंडर के क्रम में छँटता है। फ़ंक्शन डेटाबेस अनुसार बदलते हैं।
अभ्यास: YYYY-MM के month और COUNT(*) AS total, महीने अनुसार समूह और क्रम।
Hinglish mein samjhein
LOWER/UPPER case aur LENGTH characters deta hai. SQLite ka dedicated date type nahi. YYYY-MM-DD text calendar order mein sort hota hai. Date functions dialect-specific hain.
Practice: YYYY-MM month aur order COUNT(*) AS total, month group aur sorted.
A small SQL example
SELECT id, strftime('%Y-%m',order_date) AS month FROM orders ORDER BY id;Examples use the fictional shop database bundled with the SQL playground: customers, products, orders, order_items and employees. The engine is SQLite; other SQL dialects may differ.
Try this example in the SQL playground →Practise this idea
Return month and order count as total, grouped and ordered by YYYY-MM month.
Check answer & explanation
SELECT strftime('%Y-%m',order_date) AS month,COUNT(*) AS total FROM orders GROUP BY strftime('%Y-%m',order_date) ORDER BY month;strftime('%Y-%m', order_date) extracts the month in SQLite. Grouping by that expression gives one order count per month.
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Check your understanding
Portable date functions are…
Check the quiz answer
Dialect-dependent
LOWER and UPPER change text case; LENGTH counts characters. SQLite stores date-like values as text, real or integer formats, not a dedicated date type. ISO YYYY-MM-DD text sorts by calendar date. Functions differ across SQL dialects.
References & corrections
Use the official SQLite documentation for full language rules. Read how these lessons are made and checked. Found a mistake? Report it to Excel Keys with this lesson URL and a reproducible example.