Each field in a table has a number of features that provide additional control over how to operate the field.
The properties appear in the bottom left of the Table Design view when we have a selected field.
The properties are grouped into two tabs, the General tab, which indicate the general characteristics of the field and the Search tab on which we can define a list of valid values \u200b\u200bfor the field.
properties General tab can be changed to a data type or other properties while the Search tab change depending on the type of control associated with the field.
properties General tab can be changed to a data type or other properties while the Search tab change depending on the type of control associated with the field.
Keep in mind that if you modify the properties of a field after entering data in it can lose the data entered.
Then explain the properties we have for different types of data.
field size.
- For Text fields, this property determines the maximum number of characters you can enter in the field. Default being 50 characters and maximum value of 255.
- for numeric fields, the options are:
Byte (equivalent to one character) to store integer values \u200b\u200bbetween 0 and 255.
Integer to integer values \u200b\u200branging from -32,768 to 32,767. Longint
for integer values \u200b\u200branging from -2,147,483,648 to 2,147,483,647.
Simple to introduce E38 values \u200b\u200bbetween -3.402823 and -1.401298 E-45 for negative values, and between 1.401298 3.402823 E-45 and E38 for positive values. Double
values ranging -1.79769313486231 -4.94065645841247 E308 and E-324 for negative values, and between 1.79769313486231 and 4.94065645841247 E308 E-324 for positive values.
Replication ID AutoNumber key is used to mirror bases.
Decimal to store values \u200b\u200bbetween -10 and 10 ^ 38-1 ^ 38-1 (if we are in a database. Adp) and numbers from -10 ^ 10 ^ 28-1 and 28-1 (if we a database. accd)
values ranging -1.79769313486231 -4.94065645841247 E308 and E-324 for negative values, and between 1.79769313486231 and 4.94065645841247 E308 E-324 for positive values.
Replication ID AutoNumber key is used to mirror bases.
Decimal to store values \u200b\u200bbetween -10 and 10 ^ 38-1 ^ 38-1 (if we are in a database. Adp) and numbers from -10 ^ 10 ^ 28-1 and 28-1 (if we a database. accd)
- AutoNumber fields are integer largo.A other types of data they can specify size. Format
This property is used to customize the way present the data on screen or in a report.
can be set for all data types except AutoNumber OLE object and
can be set for all data types except AutoNumber OLE object and
- For Numeric and Currency fields, the options are:
General Number: presents the numbers as they were introduced.
Currency: presents the values \u200b\u200bintroduced with the thousands separator and the currency symbol assigned in Windows.
Euro: Use the format currency, the euro symbol.
Fixed: presents the values \u200b\u200bwithout insert.
Standard: present values \u200b\u200bwith insert.
Percentage: multiply the value by 100 and add the percent sign (%).
Scientist: shows the number to scientific notation.
Currency: presents the values \u200b\u200bintroduced with the thousands separator and the currency symbol assigned in Windows.
Euro: Use the format currency, the euro symbol.
Fixed: presents the values \u200b\u200bwithout insert.
Standard: present values \u200b\u200bwith insert.
Percentage: multiply the value by 100 and add the percent sign (%).
Scientist: shows the number to scientific notation.
- Fields Date / Time formats have the following general
Date: if the value is only a date, not shown any hour, if the value is only an hour, did not show any date. This value is a combination of short-dated securities and Long Time. Examples: 4/3/1993, 5:34:00 PM 4/3/1993 5:34:00 PM.
Long Date: displays the date with day of the week and the whole month. Example: Monday August 21, 2000.
Medium Date: Presents the month with the first three characters. Example: 21-Aug-2000.
Short Date: shows the date with two digit day, month and year. Example: 08/01/1900.
Short Date format assumes that dates between 1/1/00 and 31/12/1929 are dated between the years 2000 and 2029 and the dates between 01/01/1930 and 31 / 12/99 belong to the interval of years between 1930 and 1999.
Long Time: presents the time in normal format. Example: 17:35:20.
Medium Time: presents the time format AM or PM. Example: 5:35 PM.
short time presents the time without the seconds. Example: 17:35.
The Yes / No fields have predefined formats Yes / No, True / False and On / Off.
Yes, True, and On are equivalent to each other, as are No, False, Off.
Note: The default for a given control Yes / No check box is so in the Datasheet view of such data appear as a checkbox and not see the effect of the Format property. If we see the effect we have to change the default control in the Search tab of the properties of the field in the Display Control property box to choose the text as we show below.
Long Date: displays the date with day of the week and the whole month. Example: Monday August 21, 2000.
Medium Date: Presents the month with the first three characters. Example: 21-Aug-2000.
Short Date: shows the date with two digit day, month and year. Example: 08/01/1900.
Short Date format assumes that dates between 1/1/00 and 31/12/1929 are dated between the years 2000 and 2029 and the dates between 01/01/1930 and 31 / 12/99 belong to the interval of years between 1930 and 1999.
Long Time: presents the time in normal format. Example: 17:35:20.
Medium Time: presents the time format AM or PM. Example: 5:35 PM.
short time presents the time without the seconds. Example: 17:35.
The Yes / No fields have predefined formats Yes / No, True / False and On / Off.
Yes, True, and On are equivalent to each other, as are No, False, Off.
Note: The default for a given control Yes / No check box is so in the Datasheet view of such data appear as a checkbox and not see the effect of the Format property. If we see the effect we have to change the default control in the Search tab of the properties of the field in the Display Control property box to choose the text as we show below.
The
Text and Memo fields do not have predefined formats for text fields will need to create custom formats. Decimal Places
This property allows us to indicate the number of decimal places you want to assign a data type Number or Currency. Mask
input mask is used to facilitate input of data input and control the values \u200b\u200busers can enter. For example, you can create an input mask for a Phone Number field that shows exactly how to enter a new number: (___) ___-____.
Access has a Wizard Mask input that helps us to establish this property, which will access by clicking on the button to the right of the property to modify the property once activated.
An input mask is a format that attach to the introduction of values \u200b\u200bin the field. As with the format input masks can be generated automatically by the corresponding generator or we can define our own input masks.
When you create an input mask, you can use special characters to make the introduction of certain information (eg, the area code of telephone number) is mandatory and others data is optional (such as telephone extension). These characters specify the data type as the number or character to be introduced to each character in the input mask. Title
This property is used to indicate how we want to display the header field. Default
The default is the value to be stored automatically in the field if we do not introduce any value. It is usually used when one knows that a particular field will be mostly the same value, this property is used to indicate or specify what will be the value and thus to be automatically entered in the field when entering data in the table.
For example if you have a Customers table with the Province field and most clients are from the Valencia province, you can enter that value in the Default Value property of the Province field and thus the time to introduce different customers will automatically be Valencia value and we will not have to type.
Validation Rule
This property allows us to control the entry of data by criteria you specify. You have to write the criteria to be met by the value entered in the field to be entered correctly.
Validation Text
This property will write the text to be displayed on screen if we introduce a value in a field that does not meet the validation rule specified in the previous property.
should be a message for the person to make a mistake when entering data, know why and can fix his mistake.
can use this property for all data types except AutoNumber and OLE object. Required
If we want a mandatory fill field will be assigned to this property set to Yes, otherwise the value will be the No.
can be used this property for all data types except AutoNumber and OLE object.
Allow Zero Length
Memo and Text fields have this property to check that no chain can enter values \u200b\u200bthat contain no characters or empty. Indexed
This property is used to establish an index of a single field. The indexes make queries based on indexed fields faster, and also accelerate the sorting and grouping.
For example, searching for employees based on a field called Name, you can create an index on this field for faster searching.
This property has three values:
No: No index.
Yes (Duplicates OK): When an index is assigned to the field and also allows duplicate values \u200b\u200b(two rows with the same value in the field).
Yes (No Duplicates): When assigned an index but allows duplicate values.
Text and Memo fields do not have predefined formats for text fields will need to create custom formats. Decimal Places
This property allows us to indicate the number of decimal places you want to assign a data type Number or Currency. Mask
input mask is used to facilitate input of data input and control the values \u200b\u200busers can enter. For example, you can create an input mask for a Phone Number field that shows exactly how to enter a new number: (___) ___-____.
Access has a Wizard Mask input that helps us to establish this property, which will access by clicking on the button to the right of the property to modify the property once activated.
An input mask is a format that attach to the introduction of values \u200b\u200bin the field. As with the format input masks can be generated automatically by the corresponding generator or we can define our own input masks.
When you create an input mask, you can use special characters to make the introduction of certain information (eg, the area code of telephone number) is mandatory and others data is optional (such as telephone extension). These characters specify the data type as the number or character to be introduced to each character in the input mask. Title
This property is used to indicate how we want to display the header field. Default
The default is the value to be stored automatically in the field if we do not introduce any value. It is usually used when one knows that a particular field will be mostly the same value, this property is used to indicate or specify what will be the value and thus to be automatically entered in the field when entering data in the table.
For example if you have a Customers table with the Province field and most clients are from the Valencia province, you can enter that value in the Default Value property of the Province field and thus the time to introduce different customers will automatically be Valencia value and we will not have to type.
Validation Rule
This property allows us to control the entry of data by criteria you specify. You have to write the criteria to be met by the value entered in the field to be entered correctly.
Validation Text
This property will write the text to be displayed on screen if we introduce a value in a field that does not meet the validation rule specified in the previous property.
should be a message for the person to make a mistake when entering data, know why and can fix his mistake.
can use this property for all data types except AutoNumber and OLE object. Required
If we want a mandatory fill field will be assigned to this property set to Yes, otherwise the value will be the No.
can be used this property for all data types except AutoNumber and OLE object.
Allow Zero Length
Memo and Text fields have this property to check that no chain can enter values \u200b\u200bthat contain no characters or empty. Indexed
This property is used to establish an index of a single field. The indexes make queries based on indexed fields faster, and also accelerate the sorting and grouping.
For example, searching for employees based on a field called Name, you can create an index on this field for faster searching.
This property has three values:
No: No index.
Yes (Duplicates OK): When an index is assigned to the field and also allows duplicate values \u200b\u200b(two rows with the same value in the field).
Yes (No Duplicates): When assigned an index but allows duplicate values.
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