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v5:dictionary:column_attributes

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v5:dictionary:column_attributes [2016/02/29 00:42] – mnewnhamv5:dictionary:column_attributes [2024/08/31 16:26] (current) – multiple column definitions separated by comma dregad
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 ======= Dictionary Column Attributes ======= ======= Dictionary Column Attributes =======
-<WRAP todo> 
-Add Argument Definitions 
-</WRAP> 
 ====== Description ====== ====== Description ======
-When creating a column in a table using the dictionary methods, the information provided must confirm to the following specification. Each column created has a number of mandatory and optional parameters. +When creating a column in a table using the dictionary methods, the information provided must conform to the following specification. Each column created has a number of mandatory and optional parameters. 
--------------------------------- +
-<WRAP right info 300px> +
-$fields is a string, not an array +
-</WRAP>+
 ====== Basic Syntax ====== ====== Basic Syntax ======
 +
 The basic syntax of the attributes is as follows:  The basic syntax of the attributes is as follows: 
  
-  * All the information for the column must occur on a single line. +  * All the information for a given column must occur on a single line. 
 +  * Multiple columns definitions must be separated by a comma '',''
   * The line ending may be a newline or carriage return/newline combination.    * The line ending may be a newline or carriage return/newline combination. 
   * Each attribute must be separated by at least one tab or space.    * Each attribute must be separated by at least one tab or space. 
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 =======  Attributes ===== =======  Attributes =====
 ===== Column Name ===== ===== Column Name =====
-  * The column name must conform to any database specific standards related to naming and length. +  * The column name must conform to any database specific standards related to naming and length. If the name contains spaces, then it should be surrounded by backticks '' `col with spaces` ''. Note that this is an internal designator, and does not represent the character used by the database in SQL statements.                                                          
- +
 ===== Meta Attributes ===== ===== Meta Attributes =====
   * The column attributes in terms of type and length **must** be specified in terms of ADODb [[v5:dictionary:metatype|metaType]] descriptions, not the database definition for the type.   * The column attributes in terms of type and length **must** be specified in terms of ADODb [[v5:dictionary:metatype|metaType]] descriptions, not the database definition for the type.
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 </WRAP> </WRAP>
 ==== AUTO or AUTOINCREMENT ==== ==== AUTO or AUTOINCREMENT ====
-Creates the column as auto-increment. Support for this varies from one database to another. Some databases designate a field with an auto-increment flag as the primary key.+Creates the column as auto-increment. Support for this varies from one database to another. Some databases designate a field with an auto-increment flag as the primary key, and most databases only allow a single column in a table to be designated as auto-increment.
  
 ----------------------- -----------------------
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 </WRAP> </WRAP>
 ==== CONSTRAINT ==== ==== CONSTRAINT ====
 +Adds a constraint to column. The syntax for the constraint must be defined as required by the database.
 -------------------------- --------------------------
 <WRAP right box 150px> <WRAP right box 150px>
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 </WRAP> </WRAP>
 ==== DEF or DEFAULT ==== ==== DEF or DEFAULT ====
-** DEF ** indicates a default value for a column when a row is created. Some databases also require a field with a default value to be designated as NOT NULL, so that is automatically added to the column string+** DEF ** indicates a default value for a column when a row is created. Some databases also require a field with a default value to be designated as NOT NULL, so that is automatically added to the column string. For dynamically created dates or timestsamps, see the options below.
 --------------------------- ---------------------------
 +<WRAP right box 150px>
 +** Usage: Column **
 +</WRAP>
 ==== DEFDATE ==== ==== DEFDATE ====
 +Indicates if the column (metaType **D** or **T**) should be defaulted to current date when a column is created. This differs from the **DEFTIMESTAMP** option below in that it only contains the date portion of a timestamp.
 -------------------------- --------------------------
 +<WRAP right box 150px>
 +** Usage: Column **
 +</WRAP>
 ==== DEFTIMESTAMP ==== ==== DEFTIMESTAMP ====
 +Indicates if the column (metaType **D** or **T**) should be defaulted to current timestamp when a column is created.
 -------------------------- --------------------------
 <WRAP right box 150px> <WRAP right box 150px>
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 </WRAP> </WRAP>
 ==== ENUM ==== ==== ENUM ====
-In databases that support the ENUM datatype, append a parenthesized, quoted list of enum values +In databases that support the //**ENUM**// datatype, append a parenthesized, quoted list of enum values 
   ENUM('lions','tigers','halibut')   ENUM('lions','tigers','halibut')
      
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 ----------------------------------- -----------------------------------
 +<WRAP right box 150px>
 +**Usage: Column**
 +</WRAP>
 ==== INDEX ==== ==== INDEX ====
 +Creates a single column index using the same name as the column, with 'idx_' prepended to the name, e.g. a column of name ''column1'' will create an index of name ''idx_column1''.
 ------------------------------- -------------------------------
-==== KEY ==== 
  
---------------------------------+<WRAP right box 150px> 
 +** Usage: Any ** 
 +</WRAP>
 ==== NOQUOTE ==== ==== NOQUOTE ====
 +Prevents ADOdb from applying the normal quoting rules to tables, columns and indexes. For example, a column name that contains a special character such as  //**some-column**// will be automatically quoted to **//'some-column'//**. This tag prevents the behavior.
 -------------------------------- --------------------------------
 <WRAP right box 150px> <WRAP right box 150px>
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 </WRAP> </WRAP>
 ==== NOTNULL ==== ==== NOTNULL ====
 +Flags the column so that a NULL value cannot be inserted. For columns that are Auto-Increment or a Primary Key, this option is often implied.
 ---------------------------- ----------------------------
 <WRAP right box 150px> <WRAP right box 150px>
-**Usage: Index**+**Usage: Column**
 </WRAP> </WRAP>
-==== PRIMARY ====+==== PRIMARY or KEY ==== 
 +Indicates if the column is part of the [[wp>Unique Key|Primary Key]] of the table.
 --------------------------- ---------------------------
 <WRAP right box 150px> <WRAP right box 150px>
-** Usage: Index **+** Usage: Column**
 </WRAP> </WRAP>
 +
 ==== UNIQUE ==== ==== UNIQUE ====
 ** UNIQUE ** is an option against a key and indicates that duplicate values across all columns in the key are not allowed. ** UNIQUE ** is an option against a key and indicates that duplicate values across all columns in the key are not allowed.
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 </WRAP> </WRAP>
 ==== UNSIGNED ==== ==== UNSIGNED ====
 +Creates an unsigned integer.
v5/dictionary/column_attributes.1456702951.txt.gz · Last modified: (external edit)