Accuracer: The First And Only BDE Alternative
Client-Server Single-File Embedded Database for Delphi / C++Builder / Kylix
Introduction
Accuracer SQL supports these operator categories:
| · | String concatenation operator
|
Arithmetic Operators
Arithmetic operators perform mathematical operations on two expressions of any of the data types of the numeric data type category.
Operator
|
Meaning
|
+ (Add)
|
Addition
|
- (Subtract)
|
Subtraction
|
* (Multiply)
|
Multiplication
|
/ (Divide)
|
Division
|
Example:
SELECT (Price * Quantity) AS Total
FROM Order
Comparison Operators
Comparison operators test whether or not two expressions are the same. Comparison operators can be used on all expressions except expressions of the BLOB, Memo, FmtMemo or Graphic data types.
Operator
|
Meaning
|
=
|
Equal to
|
>
|
Greater than
|
<
|
Less than
|
>=
|
Greater than or equal to
|
<=
|
Less than or equal to
|
<>
|
Not equal to
|
The result of a comparison operator has the Boolean data type, which has three values: TRUE, FALSE, and UNKNOWN. Expressions that return a Boolean data type are known as Boolean expressions.
If an operator that has one or two NULL expressions returns UNKNOWN.
Expressions with Boolean data types are used in the WHERE clause to filter the rows that qualify for the search conditions
Example:
SELECT *
FROM Orders
WHERE (TaxRate > 0)
Logical Operators
Logical operators test for the truth of some condition. Logical operators, like comparison operators, return a Boolean data type with a value of TRUE or FALSE.
Operator
|
Meaning
|
AND
|
TRUE if both Boolean expressions are TRUE.
|
BETWEEN
|
TRUE if the operand is within a range.
|
IN
|
TRUE if the operand is equal to one of a list of expressions.
|
LIKE
|
TRUE if the operand matches a pattern.
|
NOT
|
Reverses the value of any other Boolean operator.
|
OR
|
TRUE if either Boolean expression is TRUE.
|
IS NULL
|
TRUE if Boolean expression is UNKNOWN
|
Examples:
SELECT *
FROM Customer
WHERE (Company LIKE '%Club%')
SELECT *
FROM Orders
WHERE (ShipToCity IS NOT NULL)
SELECT *
FROM Orders
WHERE (TaxRate BETWEEN 0 and 5) AND (AmountPaid > 1)
SELECT *
FROM Orders
WHERE (ShipVIA IN ('UPS', 'DHL'))
String Concatenation Operator
The string concatenation operator allows string concatenation with the addition sign (+) or concatenation sign (||), which is also known as the string concatenation operator.
Example:
SELECT (FirstName + ' ' + LastName) AS Name
FROM Customers
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