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SQL “select where not in subquery” returns no results
Disclaimer: I have figured out the problem (I think), but I wanted to add this issue to Stack Overflow since I couldn't (easily) find it anywhere. Also, someone might have a better answer than I do.
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How to use GROUP_CONCAT in a CONCAT in MySQL
If I have a table with the following data in MySQL:
7 Answers
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SQL - Update multiple records in one query
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Try either multi-table update syntax
UPDATE config t1 JOIN config t2
ON t1.config_name = 'name1' AND t2.config_name = 'name2'
SET t1.config_value = 'value',
t2.config_value = 'value2';
Here is SQLFiddle demo
or conditional update
UPDATE config
SET config_value...
Get ID of last inserted document in a mongoDB w/ Java driver
Is there an easy way to get the ID (ObjectID) of the last inserted document of a mongoDB instance using the Java driver?
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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
I have a table with existing data. Is there a way to add a primary key without deleting and re-creating the table?
4 Answer...
How to include layout inside layout?
How to include layout inside layout in Android?
6 Answers
6
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How do I get the “id” after INSERT into MySQL database with Python?
I execute an INSERT INTO statement
5 Answers
5
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Define variable to use with IN operator (T-SQL)
I have a Transact-SQL query that uses the IN operator. Something like this:
14 Answers
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Rails auto-assigning id that already exists
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Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SE...
Insert auto increment primary key to existing table
I am trying to alter a table which has no primary key nor auto_increment column. I know how to add an primary key column but I was wondering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it man...