Naming Conventions
When you create a database, Pervasive PSQL allows you to assign a descriptive name to each database component. Users and applications refer to the components of the database using these names. This section outlines the conventions to which you must adhere when naming database components.
For more information, see Identifier Restrictions by Identifier Type in Advanced Operations Guide.
Unique Names
The following database components must have unique names within a dictionary:
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Tables
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Views
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Indexes
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Keys
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User names
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Group names
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Stored procedures
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Triggers
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Column names within a single table
Names for parameters and variables must be unique within a SQL statement. Because Pervasive PSQL keywords are reserved words, you cannot use them for naming database components or in parameter names and variables. See SQL Reserved Words in SQL Engine Reference for a list of reserved keywords.
When a column name is repeated in different tables, you can qualify it in each table by preceding it with the relevant table name or alias name. For example, you can refer to the ID column in the Student table as Student.ID. This is a fully qualified column name, and the table name (Student) is the column qualifier.
Valid Characters
Following are the valid characters for the names of database components at the SQL level, and for variables and parameter names:
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a through z
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A through Z
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0 through 9
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_ (underscore)
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^ (caret)
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~ (tilde)
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$ (dollar sign)
*Note: The name of a database component must begin with a letter. If you specify the name of a database component or a parameter name that does not follow these conventions, specify the name in double quotes (such as “name”).
Maximum Name Lengths
Pervasive PSQL restricts the maximum length of database component names in a dictionary. See Identifier Restrictions by Identifier Type in Advanced Operations Guide and Table 19, Limits/Conditions of Pervasive PSQL Features, in SQL Engine Reference.
Case Sensitivity
Pervasive PSQL is case-sensitive when you are defining database component names. If you create a table named TaBLe1, Pervasive PSQL stores the table name in the dictionary as TaBLe1. With the exception of user names, user group names, and passwords, Pervasive PSQL is case-insensitive after you define the component name. After defining the table TaBLe1, you can refer to it as table1.
User names, user group names, and passwords are case-sensitive in Pervasive PSQL. For example, when you log in as the master user, you must specify the user name as Master.
When retrieving data, Pervasive PSQL displays names for tables, views, aliases, and columns based on the case in which they were created.
SELECT *
FROM Course#
Pervasive PSQL returns the column names as follows:
"Name", "Description", "Credit_Hours", "Dept_Name"