SQL> insert into table_b values(4); 1 row created. SQL> insert into table_b values(3); 1 row created. 现在我们将执行一个查询,通过使用IN运算符从table_b检查其值来检查在table_a中值的存在性。 SQL> select * from table_a where a in (select * from table_b); A --- 3 执行以下查...
4.3.1 Use Nested IF Statements In this exercise, you use nested IF statements. This script converts the value of a temperature from one system to another. If the temperature is supplied in Fahrenheit, it is converted to Celsius, and vice versa. Create the following PL/SQL script: -- ch0...
2 Overview of PL/SQL 3 PL/SQL Language Fundamentals Character Sets Lexical Units Declarations References to Identifiers Scope and Visibility of Identifiers Assigning Values to Variables Expressions Error-Reporting Functions Conditional Compilation 4 PL/SQL Data Types 5 PL/SQL Control Statements 6 PL/SQL...
Unlike the Switch form of the CASE statement, the WHEN statements in the If form allow comparison operators; a WHEN condition of WHEN < 0 THEN 'Under Par' is legal. CASEStarts the CASE statement. Has to be followed by one or more WHEN and THEN statements, an optional ELSE statement, ...
performance. Performance may not matter that much to some user depending on what they are trying to do but for me database is one of the key elements for getting good performance from your application. Rather than using the CASE statement and LEFT outer joins just use IF ELSE statements ...
Best practice to handle the paging and performance in SQL Stored procedure Best Practice: Use of semi-colon to terminate statements; Best practices in writing queries for huge dataset Best way to delete 311 million records from SQL Server 2017 Best way to Delete million records from billion recor...
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1.确认服务器上有两个版本的jdk,以及两个tomcat(可以使用相同版本,也可以使用不用版本的) 2.查看服务器环境变量的配置,如有相应配置,则需要根据相应环境去掉一些通用配置 如: (1)若在path路径下存在 C:\ProgramData\Oracle\Java\javapath;则需吧这个删除,否则,系统默认的jdk则是新安装的版本,导...同...
The first time I wrote it up using CASE statements in the WHERE clause and found the execution time to be horrendous, sometimes up to 3 minutes to look up an invoice. I rewrote it using dynamic SQL using sp_executesql and it was magnitudes faster, generally taking between 1 and 5 ...
DTS_E_ORACLESOURCEADAPTERSTATIC_DATAOVERFLOW DTS_E_ORACLESOURCEADAPTERSTATIC_SIGNMISMATCH DTS_E_ORACLESOURCEADAPTERSTATIC_UNAVAILABLE DTS_E_OUTPUTCOLUMNHASNOERRORCOLUMN DTS_E_OUTPUTCOLUMNNAMECONFLICT DTS_E_OUTPUTCOLUMNNOTININPUT DTS_E_OUTPUTNOTUSED DTS_E_OUTPUTREDIRECTINTRANSACTIONNOTALLOWED ...