How to query empty fields in oracle

In Oracle, you can use the select query statement with the "is" and "NULL" keywords to query empty fields. The NULL keyword is used to represent empty fields. The syntax is "select * from table name where field name. is NULL".

The operating environment of this tutorial: Windows 10 system, Oracle 11g version, Dell G3 computer.

How to query empty fields in oracle

Oracle queries empty data

where 字段名 is NULL

Empty fields are special values. This statement checks If

select gysname,gysdl,gysxl from formtable_main_674 where    gysdl=1 and gysxl=''

happens, we use is to query

select gysname,gysdl,gysxl from formtable_main_674 where    gysdl=1 and gysxl is null

Recommended tutorial: "Oracle Video Tutorial》

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