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PostgreSQL Autoincrement
I'm switching from MySQL to PostgreSQL and was wondering how I can do autoincrement values. I saw in the PostgreSQL docs a datatype "serial", but I get syntax errors when using it (in v8.0).
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Quickly reading very large tables as dataframes
...ata is passed to and from R in a binary format, which is faster.) read.csv.sql in the sqldf package, as described in JD Long's answer, imports data into a temporary SQLite database and then reads it into R. See also: the RODBC package, and the reverse depends section of the DBI package page. MonetD...
Howto: Clean a mysql InnoDB storage engine?
Is it possible to clean a mysql innodb storage engine so it is not storing data from deleted tables?
2 Answers
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How to check if a table exists in a given schema
...tion in a function. Example:
Check if sequence exists in Postgres (plpgsql)
A query like above avoids possible exceptions and is therefore slightly faster.
to_regclass(rel_name) in Postgres 9.4+
Much simpler now:
SELECT to_regclass('schema_name.table_name');
Same as the cast, but it retur...
Similarity String Comparison in Java
... Here's an article showing how combine Levenshtein with an efficient SQL query: literatejava.com/sql/fuzzy-string-search-sql
– Thomas W
Apr 26 '14 at 2:11
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世界首富换人！身价5300亿 却只开一辆破车！ - 资讯 - 清泛网 - 专注C/C++及内核技术
...新的世界首富。
而直到40岁时还是个穷裁缝的他，又是如何谱写自己传奇的呢？
奥特加贫困的童年
由于温饱难以解决，8岁那年奥特加举家搬往拉科鲁尼亚，这是个极其混乱的小渔村。13岁那年，奥特加终于迫于生活的压力辍...
SSL is not enabled on the server
...uld establish DB connection without SSL encryption, like that:
db, err := sql.Open("postgres", "user=test password=test dbname=test sslmode=disable")
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Primary key/foreign Key naming convention [closed]
... same name in both tables (convention #2), you can use the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was de...
How to install mongoDB on windows?
...efault. Lets go query that.
But how without any management studios? Unlike SQL, we have to depend on the command prompt. Yes exactly the same command prompt… our good old command prompt… Heiiiii.. Don’t get afraid yes it’s our old command prompt only.
Ok let’s go and see how we are going ...
How to enable Ad Hoc Distributed Queries
When I run a query with OPENROWSET in SQL Server 2000 it works.
4 Answers
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