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SQL Query Where Field DOES NOT Contain $x
...t is meant to be used in subqueries or with predefined lists:
-- subquery
SELECT a FROM x WHERE x.b NOT IN (SELECT b FROM y);
-- predefined list
SELECT a FROM x WHERE x.b NOT IN (1, 2, 3, 6);
If you are searching a string, go for the LIKE operator (but this will be slow):
-- Finds all rows where...
MySQL vs MongoDB 1000 reads
...s://github.com/webcaetano/mongo-mysql
10 rows
mysql insert: 1702ms
mysql select: 11ms
mongo insert: 47ms
mongo select: 12ms
100 rows
mysql insert: 8171ms
mysql select: 10ms
mongo insert: 167ms
mongo select: 60ms
1000 rows
mysql insert: 94813ms (1.58 minutes)
mysql select: 13ms
mongo inser...
“where 1=1” statement [duplicate]
...hould ignore it
No magic, just practical
Example Code:
commandText = "select * from car_table where 1=1";
if (modelYear <> 0) commandText += " and year="+modelYear
if (manufacturer <> "") commandText += " and value="+QuotedStr(manufacturer)
if (color <> "") command...
MySQL Query - Records between Today and Last 30 Days
...
You need to apply DATE_FORMAT in the SELECT clause, not the WHERE clause:
SELECT DATE_FORMAT(create_date, '%m/%d/%Y')
FROM mytable
WHERE create_date BETWEEN CURDATE() - INTERVAL 30 DAY AND CURDATE()
Also note that CURDATE() returns only the DATE portion...
How to group time by hour or by 10 minutes
...time intervals. (There is no collision between years.)
Including it in the SELECT statement will give your output a column with pretty output truncated at the level you specify.
'2000' is an "anchor date" around which SQL will perform the date math. Jereonh discovered below that you encounter an in...
Max or Default?
...d, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this:
Dim x = (From y In context.MyTable _
Where y.MyField = value _
Select CType(y.MyCounter, Integer?)).Max
Or in C#:
var x = (from y...
Store select query's output in one array in postgres
...
There are two ways. One is to aggregate:
SELECT array_agg(column_name::TEXT)
FROM information.schema.columns
WHERE table_name = 'aean'
The other is to use an array constructor:
SELECT ARRAY(
SELECT column_name
FROM information.schema.columns
WHERE table_name = ...
How to get the mysql table columns data type?
...
You can use the information_schema columns table:
SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'tbl_name' AND COLUMN_NAME = 'col_name';
share
|
im...
What must I know to use GNU Screen properly? [closed]
... target window. Warning: it will let you know if anything changes.
Want to select window 15 directly? Try these in your .screenrc file:
bind ! select 11
bind @ select 12
bind \# select 13
bind $ select 14
bind % select 15
bind \^ select 16
bind & select 17
bind * select 18
bind ( selec...
Save PL/pgSQL output from PostgreSQL to a CSV file
...e or automate, you can use Postgresql's built in COPY command. e.g.
Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER;
This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (normally called "ro...