/** Checks for type compatibility of column and expr. Returns compatible (possibly cast) expr. */
private Expr checkTypeCompatibility(Column column, Expr expr) throws AnalysisException {
// Check for compatible type, and add casts to the selectListExprs if necessary.
// We don't allow casting to a lower precision type.
Type colType = column.getType();
Type exprType = expr.getType();
// Trivially compatible.
if (colType.equals(exprType)) return expr;
Type compatibleType = Type.getAssignmentCompatibleType(colType, exprType);
// Incompatible types.
if (!compatibleType.isValid()) {
throw new AnalysisException(
String.format(
"Target table '%s' is incompatible with SELECT / PARTITION expressions.\n"
+ "Expression '%s' (type: %s) is not compatible with column '%s' (type: %s)",
targetTableName_, expr.toSql(), exprType, column.getName(), colType));
}
// Loss of precision when inserting into the table.
if (!compatibleType.equals(colType) && !compatibleType.isNull()) {
throw new AnalysisException(
String.format(
"Possible loss of precision for target table '%s'.\n"
+ "Expression '%s' (type: %s) would need to be cast to %s"
+ " for column '%s'",
targetTableName_, expr.toSql(), exprType, colType, column.getName()));
}
// Add a cast to the selectListExpr to the higher type.
return expr.castTo(compatibleType);
}
