Shulou(Shulou.com)05/31 Report--

This article mainly explains "what is the function of PostgreSQL's dump function". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn "what is the function of PostgreSQL's dump function"?

Oracle provides the hexadecimal value of the field displayed by the dump function, and PostgreSQL can be simulated by the to_hex function.

Oracle

Test script:

TEST-orcl@DESKTOP-V430TU3 > CREATE TABLE t_dumpdemo; Table created.TEST-orcl@DESKTOP-V430TU3 > TEST-orcl@DESKTOP-V430TU3 > INSERT INTO t_dumpdemo VALUES ('Chinese'); 1 row created.TEST-orcl@DESKTOP-V430TU3 > INSERT INTO t_dumpdemo VALUES ('ABCDE'); 1 row created.TEST-orcl@DESKTOP-V430TU3 > TEST-orcl@DESKTOP-V430TU3 > SELECT * FROM t_dumpdemo DESCRIPTION---- Chinese ABCDE

Dump hexadecimal valu

TEST-orcl@DESKTOP-V430TU3 > select dump (description,1016) from tasking dumpdemotion dump (DESCRIPTION,1016)-Typ=1 Len=4 CharacterSet=ZHS16GBK: d6 d0 recorder c4Typspell 1 Len=5 CharacterSet=ZHS16GBK: 41 recollection, 42meme, 43meme, 44lem45

The database is encoded in GBK, so the Chinese character encoding is GBK encoding.

PG

Create a dump function

[local]: 5432 pg12@testdb=# CREATE OR REPLACE FUNCTION dump (anynonarray) RETURNS TEXTpg12@testdb-# LANGUAGE plpgsqlpg12@testdb-# ASpg12@testdb-# $function$pg12@testdb$# DECLARE pg12@testdb$# v_hexstr TEXT;pg12@testdb$# v_hexbyte TEXT;pg12@testdb$# v_tmp TEXT;pg12@testdb$# I INT;pg12@testdb$# v_len INT;pg12@testdb$# BEGINpg12@testdb$# SELECT octet_length ($1) into vastly endowed pg12testing database # v_hexstr: = 'Len=' | | v_len | |'' Pg12@testdb$# v_tmp: =','; pg12@testdb$# FOR i in 1..v_len LOOPpg12@testdb$# select to_hex (get_byte ($1::bytea, iMei 1)) into vandalism hexbytetic pg12roomtestdbkeeper # if I = v_len thenpg12@testdb$# v_tmp: =''; pg12@testdb$# end if;pg12@testdb$# v_hexstr: = v_hexstr | | v_hexbyte | | vaccountmpppitpg12roomtestdbkeeper # END LOOP Pg12@testdb$#-- SELECT encode ($1 v_hexstr v_hexstr: = v_hexstr) #-- v_hexstr: = v_hexstr | |','| | RETURN vault hexstranspg12perfect testdatabase # function$;CREATE FUNCTIONTime: 3.621 ms

Execute the dump function to display hexadecimal values

[local]: 5432 pg12@testdb=# select dump (description) from tactile dumpdemotion; dump-Len=6 e4, b8 dump dump, e6 Len=5, 87, 41, 42, 44, 45 (2 rows) Time: 1.337 ms, so far, I believe you have a deeper understanding of "what the dump function of PostgreSQL does". You might as well do it in practice! Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.