FOR I IN TABR.FIRST .. TABR.LAST LOOP IF TABR.EXISTS(I) THEN -- 判断数据是否存在 FOR J IN 1 .. TABR(I).SEQ LOOP DBMS_OUTPUT.PUT(TABR(I).LETTER||' '); END LOOP; END IF; END LOOP; DBMS_OUTPUT.NEW_LINE ; END; 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13...
SELECT pub_name FROM publishers WHERE pub_id NOT IN (SELECT pub_id FROM titles WHERE type = 'business') 使用EXISTS 和 NOT EXISTS 引入的子查询可用于两种集合原理的操作:交集与差集。两个集合的交集包含同时属于两个原集合的所有元素。 差集包含只属于两个集合中的第一个集合的元素。 EXISTS:指定一个子...
-V, --version output version information, then exit --if-exists don't report error if user doesn't exist -?, --help show this help, then exit -h, --host=HOSTNAME database server host or socket directory -p, --port=PORT database server port -U, --username=USERNAME user name to ...
IF ( isExist=false) THEN--创建子分区表 startTime := curMM||'01 00:00:00.000'; endTime := to_char( startTime::timestamp + interval'1 month','YYYY-MM-DD HH24:MI:SS.MS'); strSQL :='CREATE TABLE IF NOT EXISTS'||TG_RELNAME||'_'||curMM||'( CHECK('||time_column_name||'...
# 修改postgresql.conf文件加入include_if_exists指令以便pg启动时加载recovery配置 # include_if_exists = '/data01/pgsql16/db/myrecovery.conf' if [ ${PGVERSION} -ge 12 ]; then sed -i -e \"\\\$ainclude_if_exists = '$(echo ${RECOVERYCONF} | sed -e 's/\//\\\//g')'\" \ ...
DROP USER [ IF EXISTS ] 名称 [, ...] 查询用户: # 用户 postgres 登录后 创建用户:命令行居然显示为 “CREATEROLE” #createuseruser1;CREATEROLE 查询pg_roles视图:多了一个 user1角色 postgres=#select*frompg_roles; rolname|rolsuper|rolinherit|rolcreaterole|rolcreatedb|rolcanlogin|rolreplication|...
-- Create "turn_result" functionCREATEFUNCTION "turn_result" ("player""move", "opponent""move") RETURNS "result" LANGUAGE plpgsql AS $$BEGIN RETURN CASE WHEN player ='rock'AND opponent ='scissors' THEN 'win' WHEN player ='rock'AND opponent ='paper' THEN 'lose' WHEN playe...
IF语句: IF … THEN … END IF IF … THEN … ELSE … END IF IF … THEN … ELSIF … THEN … ELSE … END IF 具体语法官方文档链接中可查看,现在举个小例子看一个 代码语言:javascript 复制 CREATEORREPLACEFUNCTION"public"."func1"("a"int4)RETURNS"pg_catalog"."text"AS$BODY$ ...
CREATE OR REPLACE FUNCTION execute_sql_conditionally(condition boolean) RETURNS void AS $$ BEGIN IF condition THEN EXECUTE 'SELECT * FROM table1'; ELSE EXECUTE 'SELECT * FROM table2'; END IF; END; $$ LANGUAGE plpgsql; 在上述示例中,函数execute_sql_conditionally接受一个布尔类型的参数c...
PERFORM select 1 from tbl where xxx limit 1; if found then xxx else xxx end if; 执行返回单行的表达式或QUERY,并将结果存入变量。 SELECT select_expressions INTO [STRICT] target FROM ...; INSERT ... RETURNING expressions INTO [STRICT] target; UPDATE ... RETURNING expressions INTO [STRICT] ...