MySQL automatically cast/convert a string to a number?
Does MySQL automatically casting\converting the string to numeric value? How does that conversion works? '1234'=1234 ? '1abc' = 1 ? 'text' = 1 ? Given that units.id is of bigint type, how this query will be interpreted? SELECT table.* FROM table WHERE id='text' The answers to your first three questions are: yes, yes, and no. When the string 'text' is converted to a number, it becomes the value 0 . The documentation that describes type conversion is here . For your query: SELECT table.* FROM table WHERE id='text'; The rule is captured by this excerpt from the documentation: In all other cases,