Whether the MySQL select field alias can be used in select or where

Select Column1+10 as c1,c1+10 as C2 from table1;
Want to achieve the above effect, the result in MySQL inside error, the hint can not find C1 this column;

-Different databases are not the same

It is not generally supported to continue using aliases in select or in the WHERE statement

If it is in use, you can try whether it supports:

Select Column1+10 as C1, (select C1) +10 as C2 from table1;

But in the groupby can be used

---some explanatory references

https://stackoverflow.com/questions/16715504/ mysql-define-a-variable-within-select-and-use-it-within-the-same-select/16715618#16715618

Https://stackoverflow.com/questions/6081436/how-to-use-alias-as-field-in-mysql

The SQL statement execution in MySQL is in a certain order, as follows:
1. From
2. On
3. Join
4. Where
5. GROUP BY
6. With
7. Having
8. Select
9. Distinct
Ten. ORDER BY
One. Limit
A SQL will pass these 11 steps, each step in the middle will generate a virtual table, the next step is to filter and query in the previous virtual table, the following is assumed, after 7 steps, that is, after having this step, the resulting virtual table is assumed:

id  column1 column2 alias(having后的别名)1      10       10      aaa2      20 20 bbb

Now to select this step, your query field is column1+10 as C1, then the SQL parser in this virtual table can find Column1, then the calculation and set alias success, now you want to c1+10, it found that this virtual table does not exist in this field, Then will be an error, if you want to do this: alias as XXX, then also will not error, because after having the filter, the individual name field is already in the virtual table, so the truth is very simple, select the order of execution is ranked in the 8th step, and select is for the above steps to build the virtual table operation, so you want to use the field, if the virtual table does not exist, then will be error, if the landlord of the sentence SQL to execute, it can only be changed to select Column1+10 as C1,column1+10+10 as C2 from table1;

Whether the MySQL select field alias can be used in select or where