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SQL Commands Overview

  • Articolo

Visual FoxPro supports Structured Query Language (SQL) commands. Visual FoxPro's SQL commands make use of Rushmore technology to optimize performance, and a single SQL command can be used to replace multiple Visual FoxPro commands.

Visual FoxPro supports the following SQL commands:

  • SELECT - SQL
    Specifies the criteria on which a query is based and issues the query. Visual FoxPro interprets the query and retrieves the specified data from the table(s). The SELECT command is built into Visual FoxPro like any other Visual FoxPro command. You can create a SELECT command query in these areas:
    • In the Command window.
    • In a Visual FoxPro program (like any other Visual FoxPro command).
    • In the Query Designer.
  • ALTER TABLE - SQL
    Modifies an existing table. You can modify the name, type, precision, scale, null value support, and referential integrity rules for each field in the table.
  • CREATE CURSOR - SQL
    Creates a temporary table. Each field in the temporary table is defined with a name, type, precision, scale, null value support, and referential integrity rules. These definitions can be obtained from the command itself or from an array.
  • CREATE TABLE -SQL
    Creates a table. Each new table field is defined with a name, type, precision, scale, null value support, and referential integrity rules. These definitions can be obtained from the command itself or from an array.
  • DELETE - SQL
    Marks records in a table for deletion using SQL syntax.
  • INSERT - SQL
    Appends a new record to the end of an existing table. The new record contains data listed in the INSERT command or from an array.
  • UPDATE - SQL
    Updates records in a table. The records can be updated based on the results of a SELECT - SQL statement.

See Also

CREATE CURSOR - SQL | CREATE QUERY | CREATE TABLE - SQL | DELETE - SQL | INSERT - SQL | MODIFY QUERY | SELECT - SQL | UPDATE - SQL