MySQL query data statements include: SELECT: Retrieve data ORDER BY: Sort query results GROUP BY: Group results by columns HAVING: Filter grouped data
MySQL query data statements
The statements for querying data in MySQL mainly include:
SELECT statement
is used To retrieve data from the database, the basic syntax is as follows:
<code>SELECT column_list FROM table_name [WHERE condition];</code>
Where:
column_list
: The list of columns (fields) to be retrieved. table_name
: The name of the table to retrieve data. WHERE condition
(optional): Condition for filtering data rows. ORDER BY statement
is used to sort the query results by the specified column. Its basic syntax is as follows:
<code>SELECT column_list FROM table_name [WHERE condition] ORDER BY column_name ASC/DESC;</code>
Where:
column_name
: The name of the column to be sorted. ASC
: Sort in ascending order (smallest to largest). DESC
: Sort in descending order (largest to smallest). GROUP BY statement
is used to group query results by specified columns. Its basic syntax is as follows:
<code>SELECT column_list, aggregate_function(column_name) FROM table_name [WHERE condition] GROUP BY column_name;</code>
where:
column_list
: The list of columns to retrieve, which must include the grouping column. aggregate_function
: aggregate function, such as SUM()
, COUNT()
, MAX()
, MIN()
.column_name
: Grouping column name. HAVING statement
is used to filter grouped data. Its basic syntax is as follows:
<code>SELECT column_list, aggregate_function(column_name) FROM table_name [WHERE condition] GROUP BY column_name HAVING condition;</code>
Among them:
condition
: Condition for filtering grouped data. The above is the detailed content of What are the statements for querying data in mysql?. For more information, please follow other related articles on the PHP Chinese website!