MySQL creates a MySQL series of computing fields (5)

Create a calculated field in MySQL-MySQL series (v) 1. The field has the same meaning as the column. The database column is generally called a column, A field generally refers to a calculated Field 2. concatenates A spliced field to form a single Concat () function SELECTConcat (name, (, country,) AStitleFROMcompanyOrderBYname; ASt

Create a calculated field in MySQL-MySQL series (v) 1. The field has the same meaning as the column. The database column is generally called a column, A field generally refers to a calculated Field 2. concatenates a joined field to form a single Concat () function SELECT Concat (name, '(', country ,')') AS title FROM companyOrder BY name; here's AS t

Create a calculated field in MySQL-MySQL series (5)
1. Fields

Fields are similar to column meanings. Database columns are generally called columns, and fields are generally calculated fields.

2. Splice Fields

Join -- connect values together to form a single value

Concat () function

SELECT Concat (name, '(', country, ') AS title FROM companyOrder BY name;

Here, the AS title is the alias, and the title is the calculated field.

3. Execute arithmetic calculation

Allows you to perform addition, subtraction, multiplication, and Division operations.

Select prod_num * prod_price, prod_nameFROM products

4. How to test and calculate

SELECT 3*2, 6 is returned

Select now (), returns the current time