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1052: Column 'id' in field list is ambiguous
...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
How to select all records from one table that do not exist in another table?
...
SELECT t1.name
FROM table1 t1
LEFT JOIN table2 t2 ON t2.name = t1.name
WHERE t2.name IS NULL
Q: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 wi...
How to check if a table exists in a given schema
... whether a table (or view) exists, and the current user has access to it?
SELECT EXISTS (
SELECT FROM information_schema.tables
WHERE table_schema = 'schema_name'
AND table_name = 'table_name'
);
The information schema is mainly useful to stay portable across major versions and...
How to get first and last day of previous month (with timestamp) in SQL Server
...
select DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) --First day of previous month
select DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1) --Last Day of previous month
...
jQuery remove options from select
I have a page with 5 selects that all have a class name 'ct'. I need to remove the option with a value of 'X' from each select while running an onclick event. My code is:
...
PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...
Using union and order by clause in mysql
...criteria from a table based on distance for a search on my site.
The first select query returns data related to the exact place search .
The 2nd select query returns data related to distance within 5 kms from the place searched.
The 3rd select query returns data related to distance within 5-15 kms f...
You can't specify target table for update in FROM clause
...llow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't reference that table in an inner query (you can however reference a field from that outer table...)
Th...
Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
Grouped LIMIT in PostgreSQL: show the first N rows for each group?
...
New solution (PostgreSQL 8.4)
SELECT
*
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY section_id ORDER BY name) AS r,
t.*
FROM
xxx t) x
WHERE
x.r <= 2;
sha...