方法 1：使用 `INSERT` 语句 `INSERT` 语句是 PostgreSQL 中最基本的插入数据方法。使用 `INSERT` 语句，您可以在单个表中插入单个记录或多个记录。```sql INSERT INTO users (name, email, password) VALUES ('John Doe', 'john@example.com', 'password');```方法 2：使用 `INSERT INTO` 语句（ bulk...
postgres=# \password dlf // 重新设置用户dlf的密码,然后需要 \q退出后才生效 c:\>psql exampledb < user.sql // 将user.sql文件导入到exampled数据库中 postgres=# \h select // 精细显示SQL命令中的select命令的使用方法 postgres=# \l // 显示所有数据库 postgres=# \dt // 显示当前数据库中的所有...
若字符串超出限制,PostgreSQL会立即报错,确保数据完整性。CREATE TABLE example ( short_text VARCHAR(10) ); INSERT INTO example (short_text) VALUES ('This is too long'); 上述操作中,若插入超10字符的字符串,PostgreSQL会报错,从数据库层面强制约束长度,防止存储过大值。 m.ximalaya.com/sound/841758461/?
Here, we insert three customers into the customers table in a single INSERT INTO statement. Example 3: Insert Data Using a Subquery Code: -- Insert data from one table into another using a SELECT query INSERT INTO high_value_orders (order_id, customer_id, total) SELECT order_id, customer...
Example 1: Understanding INSERT INTO SELECT Let’s discuss the concept with the help of an example so that it becomes more clear: Step 1: Create Table 1 and Insert Some Data Into it Create a table named students_info with columns StudentId, StudentName, Address, and City. ...
bigbigint);INSERTINTOexample (small,int, big)VALUES(-32768,2147483647,9223372036854775807); 小数类型 PostgreSQL支持以下小数类型: •decimal:用户指定的精度和标度,最大精度为131072位,最大标度为16383 •numeric:用户指定的精度和标度,最大精度为131072位,最大标度为16383 ...
你可以使用 INSERT 语句来给你的新表插入一些样本数据: 复制 exampledb=> INSERT INTO my_sample_table (wordlist) VALUES ('Alice'); INSERT01 1. 2. 如果你尝试在 wordlist 域中输入超过 9 个字符,则数据输入将会失败: 复制 exampledb=> INSERT INTO my_sample_table (WORDLIST) VALUES ('Alexandria'...
importjava.sql.*;publicclassPostgreSQLJDBCExample{publicstaticvoidmain(String[]args){Connectionconn=null;Statementstmt=null;ResultSetrs=null;try{Class.forName("org.postgresql.Driver");conn=DriverManager.getConnection("jdbc:postgresql://localhost:5432/yourdatabase","username","password");stmt=conn.createS...
exampledb=> ALTER TABLE my_sample_table ALTER COLUMN wordlist SET DATA TYPE VARCHAR(10); ALTER TABLE exampledb=> INSERT INTO my_sample_table (WORDLIST) VALUES ('Alexandria'); INSERT 0 1 查询表中的内容 SQL 是一种查询语言,因此你可以通过查询来查看数据库的内容。查询可以是很简单的,也可以涉及...
For example, if a row was locked but not updated because an ON CONFLICT DO UPDATE ... WHERE clause condition was not satisfied, the row will not be returned. Use of the RETURNING clause requires SELECT privilege on all columns mentioned in RETURNING. If you use the query clause to insert...