Does MySQL Automatically Convert Strings to Numbers in Comparisons?

Can MySQL Automatically Convert Strings to Numbers?

MySQL possesses the ability to automatically cast or convert strings to numeric values, facilitating seamless data manipulation. This conversion follows specific rules that govern these operations.

How String Conversion Works

• Strings like '1234' are converted to a corresponding integer (e.g., '1234' = 1234).
• Strings containing both numeric and non-numeric characters (e.g., '1abc') are converted to the numeric portion until the first non-numeric character is encountered (e.g., '1abc' = 1).
• Strings composed entirely of non-numeric characters (e.g., 'text') are converted to 0.

Interpretation of a Specific Query

Consider the following query:

SELECT table.* 
FROM table 
WHERE>

Given that the 'id' column is defined as a bigint type, how is this query interpreted?

Answer:

According to the MySQL documentation, in cases where one argument is a string and the other is a numeric type, the comparison is performed as floating-point numbers. Thus, the query above is equivalent to:

WHERE id = 0.0

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