![]() The following example creates a table named mytable containing two character fields and two memo fields. NOCPTRANS can be specified only for character and memo fields. If the table is converted to another code page, the fields for which NOCPTRANS has been specified are not translated. Prevents translation to a different code page for character and memo fields. Index tag names can contain up to 10 characters. Include TAG TagName1 to establish a relation based on an existing index tag for the parent table. If the parent table does not have a primary index, Visual FoxPro generates an error. If you omit TAG TagName1, the relationship is established using the primary index key of the parent table. Specifies the parent table to which a persistent relationship is established. Visual FoxPro will generate an error if you attempt to enter a null or duplicate value into a field used for a primary or candidate index. However, Visual FoxPro will not generate an error if you create a primary or candidate index for a field that supports null values. Null values and duplicate records are not permitted in a field used for a primary or candidate index. See INDEX for additional information on its UNIQUE option. An index created with the UNIQUE option in the INDEX command allows duplicate index keys candidate indexes do not allow duplicate index keys. ![]() The candidate index tag has the same name as the field.Ĭandidate indexes (created by including the UNIQUE option in CREATE TABLE or ALTER TABLE - SQL) are not the same as indexes created with the UNIQUE option in the INDEX command. The primary index tag has the same name as the field.Ĭreates a candidate index for the field. The data type of eExpression1 must be the same as the field's data type.Ĭreates a primary index for the field. ![]() The message is displayed only when data is changed within a Browse window or an Edit window. Specifies the error message Visual FoxPro displays when the field rule generates an error. An error is generated if the validation rule doesn't allow for a blank field value in an appended record. Whenever a blank record is appended, the validation rule is checked. lExpression1 can be a user-defined function. Specifies a validation rule for the field. However, if you omit NULL and NOT NULL and include the PRIMARY KEY or UNIQUE clause, the current setting of SET NULL is ignored and the field defaults to NOT NULL. If you omit NULL and NOT NULL, the current setting of SET NULL determines whether null values are allowed in the field. nPrecision defaults to zero (no decimal places) if nPrecision isn't included for the B, F, or N types. NFieldWidth and nPrecision are ignored for D, G, I, L, M, P, T, and Y types. Some field data types require that you specify nFieldWidth or nPrecision or both. Specifies the field name, field type, field width, and field precision (number of decimal places), respectively.įieldType is a single letter indicating the field's data type. FREE isn't required if a database isn't open. Specifies that the table will not be added to an open database. Long names can contain up to 128 characters and can be used in place of short file names in the database. ![]() A long table name can be specified only when a database is open, because long table names are stored in databases. Specifies the name of the table to create. For driver-specific information, see Driver Remarks. ![]() The Visual FoxPro ODBC Driver supports the native Visual FoxPro language syntax for this command. Creates a table having the specified fields. ![]()
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