The correlation ID is used to qualify column names for join conditions, columns, sort conditions, and row conditions.
There are three types of DSNs:
On the Internet the hostname is an ASCII string, e.g. "foldoc.doc.ic.ac.uk" which, consists of a local part (foldoc) and a domain name (doc.ic.ac.uk). The hostname is translated into an Internet address either via the /etc/hosts file, NIS or by the Domain Name System (DNS) or resolver.
It is possible for one computer to have several hostnames (aliases) though one is designated as its canonical name.
Database servers specify rules for where host variables can appear in a query. Refer to documentation for your database server for these rules.
Host variables must have a specific data type. A value that you provide for a host variable must conform to that variable's data type.
Normal characters include uppercase letters, digits, _, @, # and $. Enclose special characters in quotes. If the identifier includes a quote character, double each occurrence of the quote character and enclose the entire identifier in quote characters, such as pro"ject, would be "pro""ject". If you use lowercase letters and do not enclose the identifiers in quotes, and lowercase letters are changed to uppercase.
LOB values may or may not be stored inline with other row data in the database. In either case, LOBs have the full transactional support of the database server. A database table stores a LOB locator which points to the LOB value which may be in a different storage space.
Use the percent character to match a string of any length containing any characters. Use the underscore character to match a single character.
An application can submit statements to ODBC using the ODBC flavor of SQL. ODBC then translates these to whatever flavor the database understands. ODBC is based on Call-Level Interface and was defined by the SQL Access Group.
A procedure is a set of commands that enable you to run queries, print reports, import and export data, and perform other functions with a single command.
Procedure comments begin with two hyphens (- -) and can continue to the end of the line on which they appear. You can include as many comments as you want in a procedure. A procedure's comments, including the hyphens, are ignored by QMF for Windows until you remove the hyphens (uncomment) or remove the comments.
Query comments begin with two hyphens (- -) and can continue to the end of the line on which they appear. The query comments and hyphens are ignored by QMF for Windows and the database server at which you run the query. For example:
SELECT ID, NAME --names of the columns used FROM Q.STAFF -- the table containing these columns
It was designed so that it would be truly easy to use for both professionals and casual users and was designed to work in several diverse application areas -- such as personal programming, command processing, application macro processing and application prototyping -- where different languages are typically used. It is, however, designed to be platform-independent.
When a static query is executed, the database server uses the SQL text bound into the package, rather than the SQL text currently appearing in the query window. Static queries are more resource efficient than dynamic queries, but static queries cannot be edited.
Substitution variables must begin with an ampersand (&) and can contain up to 18 characters, which can be alphabetic, numeric or one of the following characters: [ ! $ ~ { } ? @ # % \ _.
CPI-C enables application programs distributed across a network to work together. By communicating with each other and exchanging data, they can accomplish a single processing task, such as querying a remote database.
In QMF for Windows, the packages wizard creates the required database objects and binds the required packages during server setup. TCP/IP, SNA, and CLI packages must be bound.