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Strange SQLAlchemy error message: TypeError: 'dict' object does not support indexing
I am using hand crafted SQL to fetch data from a PG database, using SqlAlchemy. I am trying a query which contains the SQL like operator '%' and that seems to throw SqlAlcjhemy through a loop:
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SQL how to make null values come last when sorting ascending
I have a SQL table with a datetime field. The field in question can be null. I have a query and I want the results sorted ascendingly by the datetime field, however I want rows where the datetime field is null at the end of the list, not at the beginning.
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Which method performs better: .Any() vs .Count() > 0?
...but if you have part of code that's slow and it uses EF, test with direct TSQL and compare performance rather than relying on assumptions (that .Any() is ALWAYS faster than .Count() > 0).
While I agree with most up-voted answer and comments - especially on the point Any signals developer inten...
MySql export schema without data
I'm using a MySql database with a Java program, now I want to give the program to somebody else.
13 Answers
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Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...ith (as follows): DECLARE @Table TABLE (CompareMessage VARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL)
– FrostbiteXIII
Jun 23 '14 at 10:57
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How do I list all tables in a schema in Oracle SQL?
How do i list all tables in a schema in Oracle SQL?
14 Answers
14
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What is the reason not to use select *?
...on. A few things off the top of my head ....
If you specify columns in a SQL statement, the SQL execution engine will error if that column is removed from the table and the query is executed.
You can more easily scan code where that column is being used.
You should always write queries to bring ba...
PadLeft function in T-SQL
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SQL Server now supports the FORMAT function starting from version 2012, so:
SELECT FORMAT(id, '0000') FROM TableA
will do the trick.
If your id or column is in a varchar and represents a number you convert first:
SELECT...
SQL keys, MUL vs PRI vs UNI
What is the difference between MUL , PRI and UNI in MySQL?
4 Answers
4
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INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...