Whena query uses literals, the optimizer can use theliteral values to find the best plan. However, when a query uses bindvariables, the optimizer must select the best plan without the presence ofliterals in the SQL text. This task can be extremely difficult. By peeking at bind values the ...
1CREATEORREPLACEPACKAGE panel_period_pkgAS2TYPE ppidtabletype IS TABLE OF NUMBER;--PL/SQL集合,非SQL中可见3FUNCTIONalloc_to_dp(p_strINVARCHAR2,4p_display_period_idINNUMBER,5p_user_idINVARCHAR2)RETURNVARCHAR2;6FUNCTIONcreate_ppa_list_from_string(p_strINVARCHAR2)7RETURNppidtabletype;8ENDpanel_pe...
2. Sql的执行过程和parse分类,oracle运行sql时,过程如下: (1). Sql cursor是否open?如果是则跳到5) 这种情况即为no parse,为方便比较,我们也作为parse的一种类型 (2). cursor是否在session cache中(pga),如果存在,则跳到5)这种情况oracle专家tom称其softer soft parse (3). 进行syntax check和 semantic che...
This Note illustrates two scenarios that can result in the "Bind variable ... not declared" error along with an explanation as to why in conjunction to steps on how to resolve this error. Scenario 1: Cause Sign In To view full details, sign in with your My Oracle Support account. Re...
Hi all, when we run an SQL with bind variables in Toad for ORACLE (tried 13.2.0.258 and 12.6.0.53) on different computers with different ORACLE Connectors (12-19) on a ORACLE DB 12.2.0.1, it is so horrible slow (up to…
使用绑定变量的重要性:如果不使用绑定变量而使用常量,会导致大量硬解析。由于硬解析的种种危害,不使用绑定变量往往是影响oracle性能和扩展性的最大问题 以下为一些错误写法和正确写法的例子 1. PLSQL中普通查询 (1). 错误写法 SELECT * FROM emp WHERE empno=123; ...
Whena query uses literals, the optimizer can use theliteral values to find the best plan. However, when a query uses bindvariables, the optimizer must select the best plan without the presence ofliterals in the SQL text. This task can be extremely difficult. By peeking at bind values the ...
Name SQL-20: Bind, do not concatenate, variable values into dynamic SQL strings. Synopsis When you bind a variable value into a dynamic SQL string, you insert a “placeholder” into the … - Selection from Oracle PL/SQL Best Practices [Book]
Oracle 是支持数组处理功能的数据源的示例。 实现此功能的另一种方法是让驱动程序生成一批 SQL 语句,为参数数组中的每个参数集生成一个 SQL 语句,并执行批处理。 参数数组不能与 UPDATE WHERE CURRENT OF语句一起使用。 处理参数数组时,单个结果集/行计数(每个参数集各有一个)可用,或者结果集/行计数可以汇总为一...
/* Oracle */ CREATE or replace PROCEDURE test_pg.calc_stats_new1 ( a NUMBER, b NUMBER, result out NUMBER ) IS BEGIN result:=a+b; END; / /* Testing */ set serveroutput on DECLARE a NUMBER := 4; b NUMBER := 7; plsql_block VARCHAR2(100); output num...