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belongs_to through associations
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I'd like to know myself. Everything I tried fired 3 selects. You can specify a "-> { joins :something }" lambda on an association. The join is fired but subsequently another select anyway. I wasn't able to tune this up.
– Renra
Oct 21 ...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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follo...
ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
... SET NAMES utf8
# query before fetching rows to index
sql_query = SELECT *, id AS pid, CRC32(safetag) as safetag_crc32 FROM hb_posts
sql_attr_uint = pid
# pid (as 'sql_attr_uint') is necessary for sphinx
# this field must be unique
# that is why I like sphinx
# you ...
Why should we typedef a struct so often in C?
...me as a non-tag name is in (POSIX or Unix) program with the int stat(const char *restrict path, struct stat *restrict buf) function. There you have a function stat in the ordinary name space and struct stat in the tag name space.
– Jonathan Leffler
Jun 5 '16 a...
Why is iostream::eof inside a loop condition (i.e. `while (!stream.eof())`) considered wrong?
...ere's an extra \n at the end. I've covered this in another answer. Reading chars is a different matter because it only extracts one at a time and doesn't continue to hit the end.
– Joseph Mansfield
Apr 6 '13 at 16:59
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Simplest way to read json from a URL in java
...tStreamReader;
import java.io.Reader;
import java.net.URL;
import java.nio.charset.Charset;
import org.json.JSONException;
import org.json.JSONObject;
public class JsonReader {
private static String readAll(Reader rd) throws IOException {
StringBuilder sb = new StringBuilder();
int cp;
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Unable to open project… cannot be opened because the project file cannot be parsed
...here projectname will be the name of your project. Now after right clicked select Show Packages Contents. After that open your projectname.pbxproj file in a text editor. Now search for the line containing <<<<<<< .mine, ======= and >>>>>>> .r. For example in...
Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
Does a break statement break from a switch/select?
I know that switch / select statements break automatically after every case. I am wondering, in the following code:
6 Ans...
List all tables in postgresql information_schema
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You should be able to just run select * from information_schema.tables to get a listing of every table being managed by Postgres for a particular database.
You can also add a where table_schema = 'information_schema' to see just the tables in the informat...