![]() ![]() For ENUM, the default is the first enumeration value. For string types (other than ENUM), the default value is the empty string.(This actually a bit more complicated for fields with the type TIMESTAMP.) For date and time types, the default is the appropriate “zero” value for the type.For numeric types, the default is typically zero.In MySQL, implicit defaults are determined as follows: However, if strict SQL mode is *not enabled,* MySQL sets the column to the implicit default value for the column data type rather than failing. (Note: In the case of a multi-row statement on a non-transactional table, an error occurs, but if this happens for the second or subsequent row of the statement, the preceding rows will have been inserted.) If strict SQL mode is enabled, an error will indeed occur and the statements will be rolled back. So accordingly, these two INSERT statements should fail since they don’t specify a value for one or more of these columns. ![]() Since the text1 and text2 columns are marked as NOT NULL and have no explicit DEFAULT clauses, attempts to insert implicit NULL values into these columns should presumably fail (note that you can use the SHOW CREATE TABLE statement to see which columns have an explicit DEFAULT clause). ![]()
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