ESQL statements overview
An ESQL statement is an instruction that represents a step in a sequence of actions or a set of declarations.
ESQL provides a large number of different statements that perform different types of operation. All ESQL statements start with a keyword that identifies the type of statement and end with a semicolon. An ESQL program consists of a number of statements that are processed in the order they are written.
As an example, consider the following ESQL program:
DECLARE x INTEGER; SET x = 42;
This program consists of two statements. The first starts with the keyword DECLARE and ends at the first semicolon. The second statement starts with the keyword SET and ends at the second semicolon. These two statements are written on separate lines and it is conventional (but not required) that they be so. You will notice that the language keywords are written in capital letters. This is also the convention but is not required; mixed case and lowercase are acceptable.
The first statement declares a variable called x of type INTEGER, that is, it reserves a space in the computer's memory large enough to hold an integer value and allows this space to be subsequently referred to in the program by the name x. The second statement sets the value of the variable x to 42. A number appearing in an ESQL program without decimal point and not within quotation marks is known as an integer literal.
ESQL has a number of data types and each has its own way of writing literal values. These are described in ESQL data types overview.
For a full description of all the ESQL statements, see ESQL statements.