大约有 44,000 项符合查询结果（耗时：0.0264秒） [XML]
Postgresql GROUP_CONCAT equivalent?
...
This is probably a good starting point (version 8.4+ only):
SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifications, below).
Prior to version...
SQL selecting rows by most recent date
...eturns a result set with ChargeId, ChargeType, and MostRecentServiceMonth
SELECT
CHARGEID,
CHARGETYPE,
MAX(SERVICEMONTH) AS "MostRecentServiceMonth"
FROM INVOICE
GROUP BY CHARGEID, CHARGETYPE
share
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SQL select join: is it possible to prefix all columns as 'prefix.*'?
... if this is possible in SQL. Say you have two tables A and B, and you do a select on table A and join on table B:
22 Answer...
What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
How do I calculate tables size in Oracle
...BLE_NAME FORMAT A32
COLUMN OBJECT_NAME FORMAT A32
COLUMN OWNER FORMAT A10
SELECT
owner,
table_name,
TRUNC(sum(bytes)/1024/1024) Meg,
ROUND( ratio_to_report( sum(bytes) ) over () * 100) Percent
FROM
(SELECT segment_name table_name, owner, bytes
FROM dba_segments
WHERE segment_type IN...
How to select first and last TD in a row?
How can you select the first and the last TD in a row?
5 Answers
5
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Fastest Way to Find Distance Between Two Lat/Long Points
...ate a SPATIAL index on these points
Use MBRContains() to find the values:
SELECT *
FROM table
WHERE MBRContains(LineFromText(CONCAT(
'('
, @lon + 10 / ( 111.1 / cos(RADIANS(@lon)))
, ' '
, @lat + 10 / 111.1
, ','
, @lon - 10 / ( 111.1 / cos(RADI...
Removing leading zeroes from a field in a SQL statement
... VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'.
...
How to get value of selected radio button?
I want to get the selected value from a group of radio buttons.
28 Answers
28
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Select tableview row programmatically
How do I programmatically select a UITableView row so that
7 Answers
7
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