oracle建立檢視包含clob欄位，報錯：資料型別不一致:應為-,但卻獲得CLOB
阿新 • • 發佈：2019-01-10
在oracle中建立檢視的時候，語句中包含有clob型別的欄位。檢視建立語句大概如下：
CREATE OR REPLACE FORCE VIEW "T_PROJECTS" ("ID", "NAME","DSC_INFO") AS
(
select a.id,a.name,'' DSC_INFO from t_project_a a
union
select b.id,b.name,b.dsc_info from t_project_b b
union
select c.id,c.name,c.dsc_info from t_project_c c
);檢查以後發現，dsc_info欄位為clob型別，起初以為是clob型別初始化的問題，於是把語句改為資料型別不一致:應為-,但卻獲得CLOB
CREATE OR REPLACE FORCE VIEW "T_PROJECTS" ("ID", "NAME","DSC_INFO") AS
(
select a.id,a.name,empty_clob() DSC_INFO from t_project_a a
union
select b.id,b.name,b.dsc_info from t_project_b b
union
select c.id,c.name,c.dsc_info from t_project_c c
);執行成功，以作記錄。CREATE OR REPLACE FORCE VIEW "T_PROJECTS" ("ID", "NAME","DSC_INFO") AS ( select a.id,a.name,'' DSC_INFO from t_project_a a union select b.id,b.name,to_char(b.dsc_info) DSC_INFO from t_project_b b union select c.id,c.name,to_char(c.dsc_info) DSC_INFO from t_project_c c );