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TheApplicationOfTheInitialValueInForms6i--Eric, Jun 14, 2009This chapter introduces the application of the initial vaule in Oracle Forms 6i.SYSTEM.RECORD_STATUSSYSTEM.RECORD_STATUS represents the status of the record where the cursor is located. The value can be one of four character strings: Value DefinitionCHANGED Indicates that a queried record's validation status is Changed. INSERT Indicates that the record's validation status is Changed and

TimingStatisticsInDifferentSqlplusVersion --Eric, Jun 13, 2009This chapter introduces the different display mode of timing statistics between SQL*PLUS 8.0 and SQL*PLUS 10.2.In the fixed SQL*PLUS version , the display mode can’t be modified.SQL*PLUS8.0In SQL*PLUS 8.0, if you execute the command “set timing on”, when we execute a SQL command , the display of timing statistics’s mode is millisecond, not our normal time. SQL*Plus: Release 8.0.6.0.0 - Production on Sat Ju

DifferenceBetweenSQLAndPLSQLScott Urman: 过程化的语言都是线性语言，例如PL/SQL，它们以Begin开始，以End结束。虽然这只是非常简化的定义，但是它指出了过程化语言与面向对象语言之间的最根本的区别，每一条语句都必须等到它之前的语句执行完毕之后才能执行。在PL/SQL的特性中，笔者所喜欢的不是它与数据库的紧密结合(虽然它与数据库结合得非常完美)，不是它拥有的高级语言的概念很功能，也不是它提供的某种功能，笔者所钟爱的是它结构化的程序设计方法。每一个BEGIN都会有一个END;每一个IF，都会有一个END IF. PL/SQL是一种结构化的、

OracleNULL --Eric, Jun 14, 2009 PL/SQL treats a string of zero-length as a NULL.A zero-length string is two single quotes without any characters in between.The following two assignments are equivalent: my_sting :=NULL; my_sting :=’’;[@more@]

OracleCharacterOracleCharacterDatatypeDatatype DefinitionVARCHAR2(size) Variable-length character string having a maximum of size bytes (up to 4000).CHAR(size) Fixed-length character data, size characters long. Maximum size is 2000.Default is 1 byte. Padded on the right with blanks to full length of size.OracleCharacterFunctionFunction DefinitionLENGTH(string) This tells the LENGTH of a string.CHR(integer) CHR gives the character with an ASCI