@Override
public void visit(SqlCoalesce sqlNode) {
out.print("SELECT ");
boolean first = true;
SqlJoin join = sqlNode.getJoinNode();
// Rough draft code.
for (Var v : sqlNode.getCoalesceVars()) {
if (!first) out.print(", ");
SqlColumn col = sqlNode.getIdScope().findScopeForVar(v).getColumn();
SqlColumn leftCol = join.getLeft().getIdScope().findScopeForVar(v).getColumn();
SqlColumn rightCol = join.getRight().getIdScope().findScopeForVar(v).getColumn();
out.print("COALESCE(");
out.print(leftCol.getFullColumnName());
out.print(", ");
out.print(rightCol.getFullColumnName());
out.print(")");
out.print(aliasToken());
out.print(col.getColumnName());
first = false;
}
// And other vars we want.
for (Var v : sqlNode.getNonCoalesceVars()) {
if (!first) out.print(", ");
first = false;
// Need generated names.
SqlColumn colSub = join.getIdScope().findScopeForVar(v).getColumn();
SqlColumn col = sqlNode.getIdScope().findScopeForVar(v).getColumn();
out.print(colSub.getFullColumnName());
out.print(aliasToken());
out.print(col.getColumnName());
}
out.ensureStartOfLine();
out.incIndent(); // INC
out.println("FROM");
join.visit(this);
out.ensureStartOfLine();
// Alias and annotations handled by outputNode
}
protected void visitJoin(SqlJoin join, String joinOperatorName) {
// TODO revisit this code. Is it now needless complex?
// Check brackets for more general SQL generation (safe mode - i.e. always bracketted?)
SqlNode left = join.getLeft();
SqlNode right = join.getRight();
// Appearance: stop nesting too much.
// Can we linearise the format? (drop indentation)
if (left.isJoin() && left.getAliasName() == null) outputNode(left, false);
else {
out.incIndent();
outputNode(left, true);
out.decIndent();
}
out.println();
// out.print(" ") ;
out.print(joinOperatorName);
annotate(join);
out.println();
// Aliasing and scoping - may need sub-SELECT - or just don't generate
// such SqlNode structures, leaving only COALESCE as the sub-SELECT case
boolean bracketsRight = true;
// if ( right.isInnerJoin() && join.isInnerJoin() && no conditions )
// bracketsRight = false ;
if (bracketsRight)
// Why?
out.incIndent();
outputNode(right, bracketsRight);
if (bracketsRight) out.decIndent();
out.println();
out.print("ON ");
if (join.getConditions().size() > 0) conditionList(join.getConditions());
else {
out.print(" ( ");
out.print(leftJoinNoConditionsString());
out.print(" )");
}
}
protected void visitJoin(SqlJoin join) {
visitJoin(join, join.getJoinType().sqlOperator());
}