/// <summary>
/// Extract Generated Column from context
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public static GeneratedColumnDefinition Extract(GeneratedColumnConstraintContext context)
{
// Get Generated Column detail: "GENERATEDALWAYSAS(hex(id))STORED"
if (context == null)
{
throw new ArgumentOutOfRangeException($"{nameof(context)} is null");
}
var predicateExpressionContext = context.GetChild <PredicateExpressionContext>();
var generatedElements = Enumerable.Range(0, context.ChildCount)
.Select(x => context.GetChild(x))
.Select(x => x.GetText())
.ToArray();
var isAlways = generatedElements.Contains("ALWAYS");
var isStored = generatedElements.Contains("STORED");
var statement = predicateExpressionContext.GetText();
var generatedColumn = new GeneratedColumnDefinition()
{
Always = isAlways,
IsStored = isStored,
Statement = statement,
};
return(generatedColumn);
}
/// <summary>
/// Listener for Generated column detection
/// </summary>
/// <param name="context"></param>
public override void EnterGeneratedColumnConstraint([NotNull] GeneratedColumnConstraintContext context)
{
base.EnterGeneratedColumnConstraint(context);
// generated column
var column = TableDefinition.LookupColumnDefinition(context);
var generatedColumn = GeneratedColumnDefinition.Extract(context);
column.GeneratedColumn = generatedColumn;
}
