Description of the functions of MYSQL where 1 = 1 Determination

So on the Internet

After checking, let's talk about it here:
1 = 1 permanent, 1 <> 1 permanent false.

1 <> 1 usage:
Used to retrieve only structures without data
For example:
Create table table_temp tablespace tbs_temp
Select * from table_ori where 1 <> 1
Create a table table_temp with the same table_ori structure, but do not use data in table_ori. (Except for the table structure

Likewise)

1 = 1
For dynamic SQL
For example, lv_string: = 'select tbl_name, tbl_desc from tbl_test where 1 = 1' | l_condition;
When the user selects the query name 'abc', l_condition: = 'and tbl_name = "abc" "; but when the user does not

During name query, l_condition is null. lv_string = 'select tbl_name, tbl_desc from tbl_test

Where 1 = 1', the operation will not go wrong, which is equivalent to no restriction on name conditions. However, if there is no 1 = 1 condition, then lv_string =

'Select tbl_name, tbl_desc from tbl_test where'; then an error is returned.

Other conditions except 1 = 1 or 1 <> 1 are the same.