Example 2: IF Statement With False Condition As discussed earlier, the PostgresIFstatement works perfectly fine only with true conditions, however, it doesn’t deal with false conditions. For instance, in the following code block, none of the specified conditions are true; let’s see how theIF...
Let’s understand the SELECT INTO statement via the following examples. Example 1: Copying Data to Regular Postgres Table We have already created a table with the following records: SELECT*FROMemp_details; Now, utilize the SELECT INTO command to copy the “emp_id” and “emp_name” columns ...
cp-r/usr/local/pgsql/data/media/ 但需要注意的是,此种方式由于比较直接,不管是否数据库有无IO情况,因此,备份的时候需要先停止数据库,恢复的时候要删除原数据库文件,重新覆盖回去后,才可以在启动数据库,如果在数据库启动的时候备份,那么,可能会造成数据备份不全,也可以理解为冷备方式。 物理备份的恢复 代码语言...
1) Basic PostgreSQL SELECT INTO statement example The following statement uses the SELECT INTO statement to create a new table called film_r that contains films with the rating R and rental duration 5 days from the film table. SELECT film_id, title, rental_rate INTO TABLE film_r FROM film...
An example: GET DIAGNOSTICS integer_var = ROW_COUNT; The second method to determine the effects of a command is to check the special variable named FOUND, which is of type boolean. FOUND starts out false within each PL/pgSQLfunction call. It is set by each of the following types of st...
Following example gives the total number of rows with a specific column value is not null. # select count(col_name) from table; 1. Following example displays the distinct number of rows for the specified column value. # select count(distinct col_name) from table; ...
PostgreSQL Create Database with Example In this article, we will discuss aboutPostgreSQL Create Databasestatement to create a new database in PostgreSQL database cluster. PostgreSQL server consists of multiple database which is called a database cluster. In other words, a database cluster is a ...
Usage example: INSERT INTO users (name, age) VALUES ('Mozart', 20); Or equivalently: INSERT INTO users (name, age, id) VALUES ('Mozart', 20, DEFAULT); SELECT currval(pg_get_serial_sequence('users', 'id')); pg_exec("INSERT INTO users (name, age) VALUES ('Bach', 15); ...
Inserting one row into a PostgreSQL table example #!/usr/bin/python import psycopg2 from config import config def insert_vendor(vendor_name): """ insert a new vendor into the vendors table """ sql = """INSERT INTO vendors(vendor_name) VALUES(%s) RETURNING vendor_id;""" conn = None ...
Example:InaDELETEstatement,forexample, you could bindinanarrayintheWHEREclauseandhave the statement be runforeachelementinthearray:DECLAREstmt VARCHAR2(200); dept_no_array DBMS_SQL.NUMBER_TABLE; c NUMBER; dummy NUMBER;begindept_no_array(1) :=10; dept_no_array(2) :=20;/* Put some values...