Select query Statement 2

First, fuzzy query

1. Grammatical structure

Select *  from where column  like ' %context% '

If you do not use the wildcard "%" when you use the LIKE operator, then the action of the similar function is the same as = =

Three ways to use 2.%

(1) Start or end match

Put% in front of the matching character or you can query with .... Data at the beginning or end

(2) Intermediate matching

You can implement a fuzzy query by placing% on both ends of the matched character

(3) matching on both ends

Put% in the middle of the matching character, you can query the data with% before the content ending with% content

3. "_" wildcard characters

The "_" wildcard representation matches any one of the characters. Use "_" when you cannot determine the exact value of one or more of these characters.

4. "[]" wildcard characters

"[]" can specify a series of characters. "[]" is typically used in combination with a variety of other wildcard characters.

Second, operator query

1.and operator Query

(1) Grammatical structure

Select *  from where  and Condition2

(2) The AND operator is a logical operator, called a logical AND operator. The query must meet two criteria at a time.

2.or operator Query

(1) Grammatical structure

Select *  from where or Condition2

(2) The OR operator is also a logical operator, called a logical OR operator, that meets one of the criteria when querying

3.in operator Query

(1) Grammatical structure

Select *  from where column inch (value_list)

Value_list represents a value that matches a query

(2) In a query, you can use the in operator if you only need to satisfy one of the conditions in multiple conditions.

4.not in operator query

(1) Grammatical structure

Select *  from where column  not inch (value_list)

(2) Display the remaining data in the query that does not contain a matching value

Select query Statement 2