Shulou(Shulou.com)06/01 Report--

Structural operation on the table

Add increase

Alter table table name drop (column character type (length)); delete

Modify reform

Desc dept; look-up table structure

Operation on record

Select column name from table name where condition lookup

Update student set column = "" where condition change

Delete from table name where conditional deletion (only delete records without deleting table structure)

Maximum value of max ()

The minimum value of function min ()

Average of avg ()

Total value of count ()

Associated database query

Select column name, column name from Table 1, Table 2 where Primary key = Foreign key and condition

Select column name, column name from Table 1 where Table 1 Primary key = (select Table 2 Foreign key from

Table 2 where conditions)

What does the like character% begin with

Order by sorting

Group by column name having condition according to what grouping statistics is in use having restriction condition

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