Oracle SQL Developer

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Utilizing the Main Features of PL/SQLCharacters such as hyphens, slashes, and spaces are not allowed. For example thefollowing identifiers are not allowed:mine&yours is not allowed because of the ampersanddebit-amount is not allowed because of the hyphenon/off is not allowed because of the slashuser id is not allowed because of the spaceYou can use upper, lower, or mixed case to write identifiers. PL/SQL is not casesensitive except within string and character literals. Every character, including dollarsigns, underscores, and number signs, is significant. If the only difference betweenidentifiers is the case of corresponding letters, PL/SQL considers them the same, as inthe following:lastname is same as LASTNAME and LastNameLastName is the same as lastname and LASTNAMELASTNAME is same as lastname and LastNameThe size of an identifier cannot exceed 30 characters. Identifiers should be descriptive.When possible, avoid obscure names such as cpm. Instead, use meaningful names suchas cost_per_thousand.Some identifiers, called reserved words or keywords, have a special syntactic meaningto PL/SQL. For example, the words BEGIN and END are reserved. Often, reservedwords and keywords are written in upper case for readability. Neither reserved wordsor keywords should be used as identifiers and the use can cause compilation errors.See Also: PL/SQL User's Guide and Reference for information onPL/SQL reserved words and keywords7.3.5 Assigning Values to a Variable With the Assignment OperatorYou can assign values to a variable in several ways. One way uses the assignmentoperator (:=), a colon followed by an equal sign, as shown in Example 7–5. You placethe variable to the left of the operator and an expression, including function calls, tothe right. Note that you can assign a value to a variable when it is declared.Example 7–5Assigning Values to Variables With the Assignment OperatorDECLARE -- declare and assiging variableswagesNUMBER(6,2);hours_worked NUMBER := 40;hourly_salary NUMBER := 22.50;bonus NUMBER := 150;country VARCHAR2(128);counter NUMBER := 0;doneBOOLEAN := FALSE;valid_id BOOLEAN;BEGINwages := (hours_worked * hourly_salary) + bonus; -- compute wagescountry := 'France'; -- assign a string literalcountry := UPPER('Canada'); -- assign an uppercase string literaldone := (counter > 100); -- assign a BOOLEAN, in this case FALSEvalid_id := TRUE; -- assign a BOOLEANEND;/7-6 SQL Developer Online Help
Utilizing the Main Features of PL/SQL7.3.6 Using LiteralsA literal is an explicit numeric, character, string, or BOOLEAN value not represented byan identifier. For example, 147 is a numeric literal and FALSE is a BOOLEAN literal.Numeric LiteralsTwo kinds of numeric literals can be used in arithmetic expressions: integers and reals.An integer literal is an optionally signed whole number without a decimal point, suchas +6. A real literal is an optionally signed whole or fractional number with a decimalpoint, such as -3.14159. PL/SQL considers a number such as 25. to be real eventhough it has an integral value.Numeric literals cannot contain dollar signs or commas, but can be written usingscientific notation. Simply suffix the number with an E (or e) followed by anoptionally signed integer, such as -9.5e-3. E (or e) stands for times ten to the powerof.Character LiteralsA character literal is an individual character enclosed by single quotes (apostrophes),such as '(' or '7'. Character literals include all the printable characters in thePL/SQL character set: letters, numerals, spaces, and special symbols.PL/SQL is case sensitive within character literals. For example, PL/SQL considers thecharacter literals 'Z' and 'z' to be different. Also, the character literals '0'..'9' arenot equivalent to integer literals but can be used in arithmetic expressions becausethey are implicitly convertible to integers.String LiteralsA character value can be represented by an identifier or explicitly written as a stringliteral, which is a sequence of zero or more characters enclosed by single quotes, suchas 'Hello, world!' and '$1,000,000'. All string literals except the null string ('')have data type CHAR.PL/SQL is case sensitive within string literals. For example, PL/SQL considers thefollowing string literals 'baker' and 'Baker' to be different:To represent an apostrophe within a string, you can write two single quotes (''),which is not the same as writing a double quote ("). Doubling the quotation markswithin a complicated literal, particularly one that represents a SQL statement, can betricky. You can also define your own delimiter characters for the literal. You choose acharacter that is not present in the string, and then do not need to escape other singlequotation marks inside the literal, such as the following string.q'!I'm using the exclamation point for a delimiter here.!'BOOLEAN LiteralsBOOLEAN literals are the predefined values TRUE, FALSE, and NULL. NULL stands for amissing, unknown, or inapplicable value. Remember, BOOLEAN literals are values, notstrings. For example, TRUE is no less a value than the number 25.Datetime LiteralsDatetime literals have various formats depending on the datetime data type, such as'14-SEP-05' or '14-SEP-05 09:24:04 AM'.Example 7–6 shows some examples of the use of literals.PL/SQL: Usage Information 7-7
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Oracle SQL DeveloperOnline HelpRele
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Contents1 SQL Developer Concepts an
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3.12 Create/Edit Index ............
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6.3.2 Updating Data With the UPDATE
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10.2.5 SQL*Plus SET Commands.......
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SQL Developer User InterfaceThe men
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SQL Developer User InterfaceThe Com
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Database Objects1.2 Database Object
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Database Objectscontaining the mast
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Database Objects■■■■■■
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Database ConnectionsWhen you start
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Running and Debugging Functions and
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Using the SQL WorksheetRelated Topi
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Using the SQL WorksheetScript Runne
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Using the SQL Worksheetmentioned in
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Reports1.9 ReportsRelated TopicsRun
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Reports1.9.3 Table reportsTable rep
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Reportsissues and vulnerabilities,
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SQL Developer Preferencesand the SQ
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SQL Developer Preferences1.10.3 Cod
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SQL Developer PreferencesSQL Develo
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SQL Developer User Information: Loc
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Supplementary Oracle Database Infor
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Creating a Table (Books)the table t
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Creating a Table (Transactions)Colu
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Creating a SequenceName: for_key_bo
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Creating a PL/SQL Procedure2.6 Crea
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Using the SQL Worksheet for Queries
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Script for Creating and Using the L
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Script for Creating and Using the L
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Check for UpdatesTo remove the effe
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Select Library3.8 Select LibraryThi
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Create PL/SQL Function, Procedure,
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Create Table (quick creation)Relate
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Create/Edit Table (with advanced op
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Create Type (User-Defined)For more
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Create/Edit ViewTest Syntax: Checks
Page 82 and 83: Configure File Type AssociationsDia
Page 84 and 85: Find/Replace TextTo add a type of o
Page 86 and 87: Save/Save As3.37 Save/Save As3.38 S
Page 88 and 89: SQL*Plus Location3-28 SQL Developer
Page 90 and 91: Managing TablesTo include lowercase
Page 92 and 93: Managing Tables4.2.4 Column Constra
Page 94 and 95: Managing Indexes4.3 Managing Indexe
Page 96 and 97: Managing Indexesuseful when all of
Page 98 and 99: Managing Views4.4 Managing Views4.3
Page 100 and 101: Managing Synonyms4-12 SQL Developer
Page 102 and 103: Storing Numeric Data■■NCHAR and
Page 104 and 105: Storing Numeric DataThe absence of
Page 106 and 107: Storing Datetime Data5.4.1.2 Using
Page 108 and 109: Storing Datetime Data5-8 SQL Develo
Page 110 and 111: Retrieving Data With Queries■■
Page 112 and 113: Retrieving Data With QueriesSee Als
Page 114 and 115: Retrieving Data With QueriesSee Als
Page 116 and 117: Transaction Control Statements6.3.2
Page 118 and 119: Using Pseudocolumns, Sequences, and
Page 124 and 125: Using SQL Data Definition Language
Page 126 and 127: Using SQL Data Definition Language
Page 128 and 129: Entering and Executing PL/SQL CodeY
Page 130 and 131: Utilizing the Main Features of PL/S
Page 148 and 149: Handling PL/SQL ErrorsTo handle une
Page 150 and 151: Handling PL/SQL ErrorsIf you redecl
Page 152 and 153: Handling PL/SQL Errors7-26 SQL Deve
Page 154 and 155: Overview of Packages and Subprogram
Page 156 and 157: Managing Packagescalling procedures
Page 158 and 159: Oracle Product-Specific PackagesTab
Page 160 and 161: Oracle Product-Specific PackagesTab
Page 162 and 163: Oracle Product-Specific Packages8-1
Page 164 and 165: Overview of Triggers9.1.1 Types of
Page 166 and 167: Overview of Triggers■■A trigger
Page 168 and 169: Designing TriggersNote: A procedure
Page 170 and 171: Using SQL*Plus■■■Running Scri
Page 172 and 173: Using SQL*PlusA SQL script file is
Page 174 and 175: Using SQL*Plus10-6 SQL Developer On
Page 176 and 177: Overview of Globalization Support
Page 178 and 179: Setting up the Globalization Suppor
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Setting up the Globalization Suppor
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SQL and PL/SQL Programming with Uni
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SQL and PL/SQL Programming with Uni
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Locale-Dependent SQL Functions with
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Locale-Dependent SQL Functions with
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COLLECTION_IS_NULL exception, 7-22c
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overview, 7-14EXPLAIN PLANexecution
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NLSSORT SQL function, 11-21NO_DATA_
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displaying output from PL/SQL, 7-9s
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disabling, 9-4enabling, 9-4error co
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Oracle SQL Developer

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