private IASTNode CreatePredicateRightValue(MySqlCommandParser.BooleanPrimaryContext ctx, IASTNode rightValue)
{
if (rightValue is ColumnSegment)
{
return(rightValue);
}
return(rightValue is SubQuerySegment subQuerySegment ? new PredicateCompareRightValue(ctx.comparisonOperator().GetText(), new SubQueryExpressionSegment(subQuerySegment))
: new PredicateCompareRightValue(ctx.comparisonOperator().GetText(), (IExpressionSegment)rightValue));
}
private IASTNode CreatePredicateRightValue(MySqlCommandParser.BooleanPrimaryContext ctx)
{
if (null != ctx.subquery())
{
new SubQuerySegment(ctx.Start.StartIndex, ctx.Stop.StopIndex, (SelectCommand)Visit(ctx.subquery()));
}
IASTNode rightValue = Visit(ctx.predicate());
return(CreatePredicateRightValue(ctx, rightValue));
}
private IASTNode CreateCompareSegment(MySqlCommandParser.BooleanPrimaryContext ctx)
{
IASTNode leftValue = Visit(ctx.booleanPrimary());
if (!(leftValue is ColumnSegment))
{
return(leftValue);
}
IPredicateRightValue rightValue = (IPredicateRightValue)CreatePredicateRightValue(ctx);
return(new PredicateSegment(ctx.Start.StartIndex, ctx.Stop.StopIndex, (ColumnSegment)leftValue, rightValue));
}
public override IASTNode VisitBooleanPrimary(MySqlCommandParser.BooleanPrimaryContext ctx)
{
if (null != ctx.comparisonOperator() || null != ctx.SAFE_EQ_())
{
return(CreateCompareSegment(ctx));
}
if (null != ctx.predicate())
{
return(Visit(ctx.predicate()));
}
if (null != ctx.subquery())
{
return(new SubQuerySegment(ctx.Start.StartIndex, ctx.Stop.StopIndex, (SelectCommand)Visit(ctx.subquery())));
}
//TODO deal with IS NOT? (TRUE | FALSE | UNKNOWN | NULL)
return(new CommonExpressionSegment(ctx.Start.StartIndex, ctx.Stop.StopIndex, ctx.GetText()));
}
