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How to change the default charset of a MySQL table?
There is a MySQL table which has this definition taken from SQLYog Enterprise :
5 Answers
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Difference between Key, Primary Key, Unique Key and Index in MySQL
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KEY and INDEX are synonyms in MySQL. They mean the same thing. In databases you would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called...
When and why are database joins expensive?
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MySQL, Oracle, SQL Server, Sybase, postgreSQL,etc. care not the order of joins. I've worked with DB2 and it also, to my knowledge, doesn't care what order you put them in. This is not helpful advice in the general case
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Is there a way to do method overloading in TypeScript?
...ally achieve the same thing with optional, or default parameters - or with union types, or with a bit of object-orientation.
The Actual Question
The actual question asks for an overload of:
someMethod(stringParameter: string): void {
someMethod(numberParameter: number, stringParameter: string): ...
MySQL: Invalid use of group function
I am using MySQL. Here is my schema:
2 Answers
2
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How do write IF ELSE statement in a MySQL query
How do I write an IF ELSE statement in a MySQL query?
5 Answers
5
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How do I convert from BLOB to TEXT in MySQL?
I have a whole lot of records where text has been stored in a blob in MySQL. For ease of handling I'd like to change the format in the database to TEXT... Any ideas how easily to make the change so as not to interrupt the data - I guess it will need to be encoded properly?
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How do you concatenate Lists in C#?
... old but I came upon this post quickly thinking Concat would be my answer. Union worked great for me. Note, it returns only unique values but knowing that I was getting unique values anyway this solution worked for me.
namespace TestProject
{
public partial class Form1 :Form
{
publ...
Preserving order with LINQ
...ement of source, selector is invoked and a sequence of values is returned.
Union - When the object returned by this method is enumerated, Union enumerates first and second in that order and yields each element that has not already been yielded.
Edit: I've moved Distinct to Preserving order base...
How to add not null constraint to existing column in MySQL
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Oddly I was getting an error (MySQL 5.6, Workbench 6.3) changing/modifying a column I'd named null_heart_rate_count, error was #1138, Invalid use of NULL value. I had to drop and add the column instead.
– William T. Mallard
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