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What GRANT USAGE ON SCHEMA exactly do?
...a schema doesn't grant rights on the tables within.
If you have rights to SELECT from a table, but not the right to see it in the schema that contains it then you can't access the table.
The rights tests are done in order:
Do you have `USAGE` on the schema?
No: Reject access.
Yes: Do...
The selected run destination is not valid for this action
...ject icon in the left hand panel. 2) In the right hand panel that appears, select Build Settings » all. 3) You'll see the option to change the SDK. Screenshot: img546.imageshack.us/img546/9808/picture3fh.png
– cwd
Dec 16 '11 at 23:12
...
Fast way to discover the row count of a table in PostgreSQL
...in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like this (extremely fast):
SELECT reltuples::bigint AS estimate FROM pg_class where relname='mytable';
How close the estimate is depends on ...
SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
IntelliJ: Working on multiple projects
...ven Projects" window (View > Tool Windows > Maven Projects) and then select the additional pom file you want to import.
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MySQL get row position in ORDER BY
...
Use this:
SELECT x.id,
x.position,
x.name
FROM (SELECT t.id,
t.name,
@rownum := @rownum + 1 AS position
FROM TABLE t
JOIN (SELECT @rownum := 0) r
ORDER BY t.name)...
What are the lesser known but useful data structures?
...s are painfully expensive, given that a pointer is generally longer than a char, which is a shame. They're only suitable for certain data-sets.
– Joe
Jan 29 '10 at 12:06
18
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How to check if my string is equal to null?
...mpty, false otherwise
return myString.isEmpty() // Returns `true` if this char sequence is empty (contains no characters), false otherwise
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Get table name by constraint name [duplicate]
...
SELECT owner, table_name
FROM dba_constraints
WHERE constraint_name = <<your constraint name>>
will give you the name of the table. If you don't have access to the DBA_CONSTRAINTS view, ALL_CONSTRAINTS or US...
CSS /JS to prevent dragging of ghost image?
...
Doesn't work in FF in combination with -moz-user-select: none. Possible solution: Add pointer-events: none.
– Cedric Reichenbach
Apr 5 '14 at 14:10
9
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