WHERE filter, the derived input table might be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP DISTINCT After the select list has been processed, the result table can optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: 132 merge different variants of the same word (see Chapter 12 for details). Sorting and duplicate-elimination are done automatically during input, as shown in this example: SELECT 'a fat cat sat on a mat

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT considerable savings because you don’t have the whole client/server communication overhead. • Elimination of additional round trips between client and server • Intermediate results that the client does

WHERE filter, the derived input table might be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP DISTINCT After the select list has been processed, the result table can optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: 125 of UNION does not contain any duplicate rows unless the ALL option is specified. ALL prevents elimination of duplicates. (Therefore, UNION ALL is usually significantly quicker than UNION; use ALL when

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT considerable savings because you don’t have the whole client/server communication overhead. • Elimination of additional round trips between client and server • Intermediate results that the client does

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT considerable savings because you don’t have the whole client/server communication overhead. • Elimination of additional round trips between client and server • Intermediate results that the client does

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT of UNION does not contain any duplicate rows unless the ALL option is specified. ALL prevents elimination of duplicates. (Therefore, UNION ALL is usually significantly quicker than UNION; use ALL when

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT of UNION does not contain any duplicate rows unless the ALL option is specified. ALL pre- vents elimination of duplicates. (Therefore, UNION ALL is usually significantly quicker than UNION; use ALL when

WHERE filter, the derived input table may be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table may optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT of UNION does not contain any duplicate rows unless the ALL option is specified. ALL prevents elimination of duplicates. (Therefore, UNION ALL is usually significantly quicker than UNION; use ALL when

WHERE filter, the derived input table might be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table can optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT merge different variants of the same word (see Chapter 12 for details). Sorting and duplicate-elimination are done automatically during input, as shown in this example: SELECT ’a fat cat sat on a mat

WHERE filter, the derived input table might be subject to grouping, using the GROUP BY clause, and elimination of group rows using the HAVING clause. SELECT select_list FROM ... [WHERE ...] GROUP BY group DISTINCT After the select list has been processed, the result table can optionally be subject to the elimination of duplicate rows. The DISTINCT key word is written directly after SELECT to specify this: SELECT merge different variants of the same word (see Chapter 12 for details). Sorting and duplicate- elimination are done automatically during input, as shown in this example: SELECT ’a fat cat sat on a mat