QT+SQL的常用语句

1. 创建表：
CREATE TABLE table_name (
column1 datatype,
column2 datatype,
column3 datatype,
...
);

2. 插入数据：
INSERT INTO table_name (column1, column2, column3, ...)
VALUES (value1, value2, value3, ...);

3. 更新数据：
UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;

4. 删除数据：
DELETE FROM table_name
WHERE condition;

5. 查询数据：
SELECT column1, column2, ...
FROM table_name
WHERE condition;

6. 排序数据：
SELECT column1, column2, ...
FROM table_name
ORDER BY column1 ASC/DESC, column2 ASC/DESC, ...;

7. 连接查询：
SELECT column1, column2, ...
FROM table1
JOIN table2
ON table1.column = table2.column;

8. 分组统计：
SELECT column1, COUNT(column2)
FROM table_name
GROUP BY column1;

9. 子查询：
SELECT column1, column2, ...
FROM table_name
WHERE column1 IN (SELECT column1 FROM table2 WHERE condition);

10. 聚合函数：
SELECT COUNT(column1), SUM(column2), AVG(column3), MAX(column4), MIN(column5)
FROM table_name;