Associative array 关联数组有点类似于java中的Map,只是在PL/SQL中,关联数组索引的数据类型只能是string类型(VARCHAR2,VARCHAR,STRING,LONG)和PLS_INTEGER。关联数组不存在为NULL的情况,所以你不能使用IS NULL和IS NOT NULL去测试它,否则无法通过编译。 定义关联数组的方式如下: TYPE 关联数组类型名称 IS TABLE OF ...
recovery_target_timeline (string)指定恢复到一个特定的时间线中。默认值是沿着基础备份建立时的当前时间线恢复。 将这个参数设置为latest会恢复到该归档中能找到的最新的时间线, 这在一个后备服务器中有用。 recovery_target_action (enum) (boolean)指定当到达恢复目标时服务器应该采取什么动作。默认值是pause, 这...
3、连接字符串中含有空值会把NULL作为 EMPTY STRING declare v_deptno dept.deptno%type; v_loc dept.loc%type; V_FLAG BOOLEAN ; V_REC BOOLEAN :=FALSE; --此值改为TRUE、NULL、FALSE进行不同的比较 V_AVA BOOLEAN:=NULL; begin V_FLAG:=V_REC AND V_AVA; IF V_FLAG=TRUE THEN DBMS_OUTPUT.PUT_...
3.1 redis主节点 # 先手动配置redis-vip地址ifconfig eth0:3 192.168.150.187/24# 安装包下载地址http://download.redis.io/releases/# 下载[root@master ~]# wget http://download.redis.io/releases/redis-6.2.9.tar.gz2、 安装gcc[root@master ~]# yum install -y gcc3、解压[root@master ~]# tar ...
Returns the numeric value of the leftmost character of the string str. Returns 0 if str is the empty string. Returns NULL if str is NULL. ASCII() works for characters with numeric values from 0 to 255. 复制 testdb=#SELECTASCII('2');+---+| ASCII('2') |+---+| 50 |+---...
if test "$(id -u)" -eq 0; then cmd= for v in PGSETUP_DEBUG PGSETUP_INITDB_OPTIONS PGSETUP_PGUPGRADE_OPTIONS; do eval var_content=\$$v test -z "$var_content" && continue cmd+=$v="$(printf %q "$var_content") " ...
const llvm::FunctionSummary *fs; llvm::StringRef modPath = gvs->modulePath(); llvm::Module *defMod; llvm::Function *funcDef; fs = llvm::cast<llvm::FunctionSummary>(gvs); if ((int) fs->instCount() > inlineState.costLimit) { ilog(DEBUG1, "ineligibile to import %s due to early...
if ('0' == NULL) printf("NULL is '0' n"); if ("" == NULL) printf("NULL is empty string n"); if (' ' == NULL) printf("NULL is space n"); if (0 == NULL) printf("NULL is 0 n"); } The output of the above program will be “NULL is 0”, so it is quite evide...
*/ finish_xact_command(); } else if (lnext(parsetree_item) == NULL) { /* * If this is the last parsetree of the query string, close down * transaction statement before reporting command-complete. This * is so that any end-of-transaction errors are reported before * the command-com...
TupIsNull(result)) { /* * If the subplan gave us something then return it as-is. We do * NOT make use of the result slot that was set up in * ExecInitAppend; there's no need for it. */ return result; } // 同步子计划结果为空, // 说明这个同步子计划执行结束,需要选择下一...