Nvl Kullanımı. Select ifnullmiddlename na from person. The oracleplsql substr functions allows you to extract a substring from a string.
Mysql has ifnull function while oracle provides nvl function. The nvl function allows you to replace null values with a default value. The above decode statement is equivalent to the following if then else statement.
The following function call.
Oracle nvl and case expression. Mysql has ifnull function while oracle provides nvl function. Data type must match with each other ie. Mysql ifnull takes two expressions and if the first expression is not null it returns the first expression.