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MySQL COUNT DISTINCT
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I love SQL because you get questions like "How do I count distinct user IDs" and the answer is just "Count(Distinct user_id)"
– Tim
Nov 13 '18 at 15:29
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Create or write/append in text file
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Oh, yes there will be, in this case use a SQL database, it has a built-in engine to avoid race-conditions. But that's a whole new question.
– Valentin Mercier
Jul 26 '14 at 15:45
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How can I turn a List of Lists into a List in Java 8?
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.collect(Collectors.toList())
This is would be similar in SQL to having SELECT statements within SELECT statements.
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Must JDBC Resultsets and Statements be closed separately although the Connection is closed afterward
...lph Stevens - You cannot count on that. I have had a situation where the MSSQL JDBC driver leaked memory because the ResultSet's were not closed, even after being garbage collected.
– Paul
Sep 8 '11 at 5:52
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PostgreSQL ERROR: canceling statement due to conflict with recovery
I'm getting the following error when running a query on a PostgreSQL db in standby mode. The query that causes the error works fine for 1 month but when you query for more than 1 month an error results.
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How can I Remove .DS_Store files from a Git repository?
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*.rar
*.tar
*.zip
# Logs and databases #
######################
*.log
*.sql
*.sqlite
# OS generated files #
######################
.DS_Store
.DS_Store?
._*
.Spotlight-V100
.Trashes
ehthumbs.db
Thumbs.db
Now, add this file to your global git config:
git config --global core.excludesfile ~/.git...
Best timestamp format for CSV/Excel?
...y user662894.
I want to add: Don't try to get the microseconds from, say, SQL Server's datetime2 datatype: Excel can't handle more than 3 fractional seconds (i.e. milliseconds).
So "yyyy-mm-dd hh:mm:ss.000000" won't work, and when Excel is fed this kind of string (from the CSV file), it will perfo...
How to get milliseconds from LocalDateTime in Java 8
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You can use java.sql.Timestamp also to get milliseconds.
LocalDateTime now = LocalDateTime.now();
long milliSeconds = Timestamp.valueOf(now).getTime();
System.out.println("MilliSeconds: "+milliSeconds);
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Suppress warning messages using mysql from within Terminal, but password written in bash script
When I tried running the following command on MySQL from within Terminal:
25 Answers
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What is the largest TCP/IP network port number allowable for IPv4?
...t for your server, but be careful some famous applications: like Microsoft SQL Server database management system (MSSQL) server or Apache Derby Network Server are already taking from this range i.e. it is not recommended to assign the port of MSSQL to your server otherwise if MSSQL is running then y...