Of course, if you have more conditions, you can add () such as: select * from tbwhere (a field =' x' ora field =' y') and b field =' zzz'.

StructuredQueryLanguage (SQL for short) is a special programming language, a database query and programming language, which is used to access data, query, update and manage relational database systems. SQL uses single quotation marks around text values (most database systems also accept double quotation marks).

Text value: This is correct: select * from Pers where first name =' bush'. This is wrong: select * from Pers where first name = bush.