本篇内容主要讲解“PostgreSQL的dump函数有什么作用”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“PostgreSQL的dump函数有什么作用”吧!

Oracle提供了dump函数显示字段的十六进制值,PostgreSQL可通过to_hex函数来进行模拟.

Oracle
测试脚本:

TEST-orcl@DESKTOP-V430TU3>CREATETABLEt_dumpdemo(descriptionvarchar(200));Tablecreated.TEST-orcl@DESKTOP-V430TU3>TEST-orcl@DESKTOP-V430TU3>INSERTINTOt_dumpdemoVALUES('中文');1rowcreated.TEST-orcl@DESKTOP-V430TU3>INSERTINTOt_dumpdemoVALUES('ABCDE');1rowcreated.TEST-orcl@DESKTOP-V430TU3>TEST-orcl@DESKTOP-V430TU3>SELECT*FROMt_dumpdemo;DESCRIPTION--------------------------------------------------------------------------------中文ABCDE

dump十六进制值

TEST-orcl@DESKTOP-V430TU3>selectdump(description,1016)fromt_dumpdemo;DUMP(DESCRIPTION,1016)--------------------------------------------------------------------------------Typ=1Len=4CharacterSet=ZHS16GBK:d6,d0,ce,c4Typ=1Len=5CharacterSet=ZHS16GBK:41,42,43,44,45

数据库是用GBK编码,因此’中文’字符编码为GBK编码.

PG
创建dump函数

[local]:5432pg12@testdb=#CREATEORREPLACEFUNCTIONdump(anynonarray)RETURNSTEXTpg12@testdb-#LANGUAGEplpgsqlpg12@testdb-#ASpg12@testdb-#$function$pg12@testdb$#DECLAREpg12@testdb$#v_hexstrTEXT;pg12@testdb$#v_hexbyteTEXT;pg12@testdb$#v_tmpTEXT;pg12@testdb$#iINT;pg12@testdb$#v_lenINT;pg12@testdb$#BEGINpg12@testdb$#SELECToctet_length($1)intov_len;pg12@testdb$#v_hexstr:='Len='||v_len||'';pg12@testdb$#v_tmp:=',';pg12@testdb$#FORiin1..v_lenLOOPpg12@testdb$#selectto_hex(get_byte($1::bytea,i-1))intov_hexbyte;pg12@testdb$#ifi=v_lenthenpg12@testdb$#v_tmp:='';pg12@testdb$#endif;pg12@testdb$#v_hexstr:=v_hexstr||v_hexbyte||v_tmp;pg12@testdb$#ENDLOOP;pg12@testdb$#--SELECTencode($1::bytea,'hex')intov_hexbyte;pg12@testdb$#--v_hexstr:=v_hexstr||','||v_hexbyte;pg12@testdb$#RETURNv_hexstr;pg12@testdb$#END;pg12@testdb$#$function$;CREATEFUNCTIONTime:3.621ms

执行dump函数,显示十六进制值

[local]:5432pg12@testdb=#selectdump(description)fromt_dumpdemo;dump-------------------------Len=6e4,b8,ad,e6,96,87Len=541,42,43,44,45(2rows)Time:1.337ms

到此，相信大家对“PostgreSQL的dump函数有什么作用”有了更深的了解，不妨来实际操作一番吧！这里是亿速云网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！