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Just how easy is it to restructure a table?
Click on any of the links below to see how easy it is to control
the way your tables are restructured. Note that all these examples assume two
things:
- You have already placed a TRestructure component on a form and
it's name is Restructure1
- You have set properties DatabaseName and TableName to appropriate
values
You should also be aware that changes are written to the table
only after a call to Apply method:
Restructure1.Apply;
At any time (before the call to Apply method) you can cancel the changes to
the table by placing a call to Cancel method:
Restructure1.Cancel;
How to:
Add a field?
with Restructure1.Field do
begin
FieldType := pxAlpha; // Paradox Alpha type
Name := 'NewFieldName';
Length := 20;
end;
Restructure1.AddField(False); // don't set validity checks
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Change a field?
with Restructure1.Field do
begin
FieldType := pxNumber; // Paradox Number type
Name := 'NewFieldName';
end;
// Change the first field and don't change validity checks
Restructure1.ChangeField(1, False);
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Delete a field?
// Drop the third field
Restructure1.DropField(3);
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Insert a field at specific position?
with Restructure1.Field do
begin
FieldType := pxTimestamp; // Paradox Timestamp type
Name := 'NewFieldName';
end;
// Insert the field as second and don't change validity checks
Restructure1.InsertField(2, False);
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Move a field?
// Move the second field to the fifth position
Restructure1.MoveField(2, 5);
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Get the field's name, size, type and
validity checks (if any)?
// After this call, Restructure1.Field.* and
// Restructure1.ValCheck.* properties are filled
// with all the information about the seventh field
Restructure1.GetFieldDesc(7);
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Access a field by its name?
// FieldByName returns field's position in the table
// You can use this function with all of the above
// method calls. For example:
//
// Restructure1.GetFieldDesc(Restructure1.FieldByName('SomeField'));
//
var
Position: Integer;
Position := Restructure1.FieldByName('FieldName');
// Note: FieldByName is not case sensitive
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Check if a field has any validity checks?
var
lVC: Boolean;
lVC := Restructure1.HasValChecks('SomeField');
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Add a validity check?
// Set the default value for a Boolean field
with Restructure1.ValCheck do
begin
DefaultValue := 'true';
end;
Restructure1.AddValCheck('SomeLogicalField');
// Set the default value for a Date field, and make it required
with Restructure1.ValCheck do
begin
DefaultValue := 'today';
Required := True;
end;
Restructure1.AddValCheck('SomeDateField');
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Change a validity check?
with Restructure1.ValCheck do
begin
DefaultValue := '16';
MinimumValue := '13';
MaximumValue := '19';
end;
Restructure1.ChangeValCheck('TeenagerAgeField');
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Delete a validity check?
// Remove all validity checks from TeenagerAgeField
Restructure1.DropValCheck('TeenagerAgeField');
// Remove only default value validity check from TeenagerAgeField
Restructure1.GetFieldDesc(Restructure1.FieldByName('TeenagerAgeField'));
Restructure1.ValCheck.DefaultValue := '';
Restructure1.ChangeValCheck('TeenagerAgeField');
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Check if the table has any referential
integrity constraints set?
var
lRI: Boolean;
lRI := Restructure1.HasRefInts;
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Add a referential integrity constraint?
with Restructure1.RefInt do
begin
MasterTableName := 'MasterTable.DB';
// Do not allow cascade changes
// (DeleteOperation is set to urRestrict by default)
ModifyOperation := urRestrict;
end;
Restructure1.AddRefInt('RefIntName', 'DetailIndexName');
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Remove (delete) a referential integrity
constraint?
Restructure1.DropRefInt('RefIntName');
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Add a master password to the table (protect
the table)?
Restructure1.AddMasterPassword('NewPassword');
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Change table's master password?
Restructure1.ChangeMasterPassword('NewPassword');
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Remove (delete) table's master password
(unprotect the table)?
Restructure1.DropMasterPassword;
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Add an auxiliary password?
// Add a password and set table rights to full
Restructure1.AddAuxPassword('NewAuxiliaryPassword', trFull);
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Change an auxiliary password?
// Change a password and/or change table rights
Restructure1.ChangeAuxPassword('OldAuxiliaryPassword', 'NewAuxiliaryPassword',
trModify);
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Remove (delete) an auxiliary password?
Restructure1.DropAuxPassword('ExistingAuxiliaryPassword');
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Set field rights for any specific auxiliary
password?
Restructure1.ChangeFieldRights('AuxiliaryPassword', 'FieldName',
frReadOnly);
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As you can see from the above examples, any change comes down to
setting a few properties and calling the appropriate method. In fact, most of
these are only one line of code!
Pricing
You can register online by clicking one of the buttons below
and download the full source code within minutes.
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Eurocard, Delta, UK and US checks, Purchase Orders and PayPal. Click the button
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the oldest online software store in the world, or ShareIt!, one of the
biggest online software stores.
| Description |
Option |
Price
|
Register secure online
|
TRestructure Pro
Single Developer License |
with source |
$129.50 |
 |
TRestructure Pro
5 Developers License |
with source |
$388.50 |
TRestructure Pro
Site License |
with source |
$1,295.00 |
TRestructure Lite
Single Developer License |
with source |
$99.50 |
|
TRestructure Lite
5 Developers License |
with source |
$298.50 |
TRestructure Lite
Site License |
with source |
$995.00 |
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