How Does MySQL Handle Implicit Data Type Conversion in Queries?

MySQL Implicit Data Type Conversion

MySQL possesses the ability to automatically cast strings to numeric values under certain circumstances.

Conversion Mechanism

• '1234' is converted to 1234 because it is an integer-like string.
• '1abc' is converted to 1 because the numeric portion of the string is identified for conversion.
• 'text' is not converted to a number because it does not contain any recognizable numeric characters.

Query Interpretation

With the given scenario, where units.id is a bigint type, the query

SELECT table.* 
FROM table 
WHERE>

will be interpreted as follows:

• 'text' is implicitly converted to 0.0 (floating-point zero).
• The WHERE clause now effectively becomes WHERE id = 0.0.
• The query will return rows where id is equal to 0 (bigint).

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