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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...
How to declare a variable in a PostgreSQL query
...ows you to return a table of temporary values.
WITH master_user AS (
SELECT
login,
registration_date
FROM users
WHERE ...
)
SELECT *
FROM users
WHERE master_login = (SELECT login
FROM master_user)
AND (SELECT registration_date
FROM ma...
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
...
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...
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 ...
How do you do a limit query in JPQL or HQL?
...
// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
share
...
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)...
MySQL Conditional Insert
...
If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = ...
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...