Progress
SQL-92
Guide and Reference
Overview
Definitions of Language Elements
- An Identifier is a user-supplied name for an element such as a table, view, cursor, or column. SQL statements use these names to refer to the elements.
- Data types control how SQL stores column values. CREATE TABLE statements specify data types for columns.
- Query expressions retrieve values from tables. Query expressions form the basis of other SQL statements and syntax elements.
- Search conditions specify a condition about a given row or group of rows that is true or false. Query expressions and UPDATE statements specify search conditions to restrict the number of rows in the result table.
- Expressions are symbols or strings of symbols used to represent or calculate a single value in a SQL statement. When SQL encounters an expression, it retrieves or calculates the value represented by the expression and uses that value when it executes the statement.
- Literals are a type of SQL expression that specify a constant value. Some SQL constructs allow literals but prohibit other forms of expressions.
- Date-time format strings control the output of date and time values. SQL interprets format strings and replaces them with formatted values.
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