I have a table and I am doing a self join on it with geo-spacial functions fro PostgreSQL. Now I am expecting to build the point of intersections of each intersection except for those that has the attribute 'tunnel_road' having same values.
Therefore I have two rows conatining the value 'tunnel' which I don't want to build a point of intersection between them.
The query I am using is the following, though it is not working properly since it still is creating a point of intersection between the two lines.
insert into temp_intersect
select nextval('road_intersection_id_seq'), a.road_id, b.road_id, st_intersection(a.road, b.road), st_centroid(st_intersection(a.road, b.road))
from polygon_road a, polygon_road b
where st_intersects(a.road, b.road) AND a.road_id < b.road_id AND a.tunnel_road != b.tunnel_road
Any suggestions please?
the following is the table from which I am getting my data. As one can notice there is two rows containing the same value for the tunnel_road column where there is the id = 47 and 73
Related
So Im trying to use INNER JOIN in my sql command because I am trying to replace the Foreign keys ID numbers with the text value of each column. However, when I use INNER JOIN, the column for "Standards" always gives me the same value. The following is what I started with
SELECT Grade_Id, Cluster_Eng_Id, Domain_Math_Eng_Id, Standard
FROM `math_standards_eng`
WHERE 1
and returns this (which is good). Notice the value of Standard values are different
Grade_Id Cluster_Eng_Id Domain_Math_Eng_Id Standard
103 131 107 Explain equivalence of fractions in special cases...
104 143 105 Know relative sizes of measurement units within o...
When I try to use Inner Join, the values for Grade_Id, Cluster_Eng_Id, and Domain_Math_Eng_Id are changed from numbers to actual text. Standard column values, however, seems to return the same value. Here is my code:
SELECT
grades_eng.Grade, domain_math_eng.Domain, cluster_eng.Cluster,
math_standards_eng.Standard
FROM
math_standards_eng
INNER JOIN
grades_eng ON math_standards_eng.Grade_Id = grades_eng.Id
INNER JOIN
domain_math_eng ON math_standards_eng.Domain_Math_Eng_Id
INNER JOIN
cluster_eng ON math_standards_eng.Cluster_Eng_Id
This is what I get when I run the query:
Grade Domain Cluster Standard
3rd Counting and cardinality Know number names and the count sequence Explain equivalence of fractions in special cases...
3rd Expressions and Equations Know number names and the count sequence Explain equivalence of fractions in special cases...
3rd Functions Know number names and the count sequence Explain equivalence of fractions in special cases.
4th Counting and cardinality Know number names and the count sequence Know relative sizes of measurement units within o...
4th Expressions and Equations Know number names and the count sequence Know relative sizes of measurement units within o...
The text value for Standard keeps on showing the same value per grade and I do not know why. 3rd Will keep showing the same thing, and then the next grade will change to a new value and repeat over and over. Lastly, each table has a 1:M relationship with standard as they each appear multiple times in the standard Table. Any advice would be greatly appreciated.
You are missing the = part of your INNER JOIN on domain_math_eng and cluster_eng. I would expect something like:
SELECT grades_eng.Grade, domain_math_eng.Domain, cluster_eng.Cluster, math_standards_eng.Standard FROM math_standards_eng
INNER JOIN grades_eng ON math_standards_eng.Grade_Id = grades_eng.Id
INNER JOIN domain_math_eng ON math_standards_eng.Domain_Math_Eng_Id = domain_math_eng.Id
INNER JOIN cluster_eng ON math_standards_eng.Cluster_Eng_Id = cluster_eng.Id
I read many threads but didn't get the right solution to my problem. It's comparable to this Thread
I have a query, which gathers data and writes it per shell script into a csv file:
SELECT
'"Dose History ID"' = d.dhs_id,
'"TxFieldPoint ID"' = tp.tfp_id,
'"TxFieldPointHistory ID"' = tph.tph_id,
...
FROM txfield t
LEFT JOIN txfielpoint tp ON t.fld_id = tp.fld_id
LEFT JOIN txfieldpoint_hst tph ON fh.fhs_id = tph.fhs_id
...
WHERE d.dhs_id NOT IN ('1000', '10000')
AND ...
ORDER BY d.datetime,...;
This is based on an very big database with lots of tables and machine values. I picked my columns of interest and linked them by their built-in table IDs. Now I have to reduce my result where I get many rows with same values and just the IDs are changed. I just need one(first) row of "tph.tph_id" with the mechanics like
WHERE "Rownumber" is 1
or something like this. So far i couldn't implement a proper subquery or use the ROW_NUMBER() SQL function. Your help would be very appreciated. The Result looks like this and, based on the last ID, I just need one row for every og this numbers (all IDs are not strictly consecutive).
A01";261511;2843119;714255;3634457;
A01";261511;2843113;714256;3634457;
A01";261511;2843113;714257;3634457;
A02";261512;2843120;714258;3634464;
A02";261512;2843114;714259;3634464;
....
I think "GROUP BY" may suit your needs.
You can group rows with the same values for a set of columns into a single row
I performed STInteract using two tables and the intersections of points onto a given polygon. I have converted all the tables to have geometries for all. I am having a problem writing the query for this. I am trying to look for the points that did not intersect.
These are my two table
PO_Database = contains the points
POLY_Database = Polygon of interest
This is my script:
SELECT GEOM
FROM [dbo].[PO_Database] as PO
JOIN [dbo].[POLY_Database] as p ON hwy.GEOM.STIntersects(p.NEATCELL) = 1
I tried changing the value from 1 to 0 but I get repeating values of the geometry for when the query is run with 0. How do I write the query to give me the names of the points that did not intersect with the polygon. Also is there a way to do checks if the intersects where done right.
If you get repeating values, you probably have multiple rows in the POLY_Database table. If you want to find the points that do not intersect any of those polygons, try this query:
SELECT GEOM
FROM [dbo].[PO_Database] as PO
WHERE NOT EXISTS (
SELECT * FROM [dbo].[POLY_Database] as p
WHERE hwy.GEOM.STIntersects(p.NEATCELL) = 1
)
I have two tables in MS Access and I am trying to add a field for one of those tables that tells which record from another table has a value that is less than the first field's value, but comes the closest? I have this query so far (just a select statement to test output and not alter existing tables), but it lists all values that are less than the querying value:
SELECT JavaClassFileList.ClassFile, ModuleList.Module
FROM JavaClassFileList, ModuleList
WHERE ModuleList.Order<JavaClassFileList.Order;`
I tried using things likeSELECT JavaClassFileList.Classfile, MAX(ModuleList.Module), which will only display the maximum module but combined it with the select statement above, but it would say that it would only return one record.
Output desired: I have some records, a, b, and c, I shall call them, each storing various information, while a is storing a value of 732 in a column, and b is storing a value of 731 in the same column. c is storing a value of 720. In another table, d is storing a value of 730 and e is storing a value of 718. I want the output like this (they are ordered largest to smallest):
a 732 d 730
b 731 d 730
c 720 e 718
There can be duplicates on the right, but no duplicates on the left. How can I get this result?
I would approach this type of query using a correlated subquery. I think the following words in Access:
SELECT jc.ClassFile,
(select top 1 ml.Module
from ModuleList as ml
where ml.[Order] < jc.[Order]
)
FROM JavaClassFileList as jc;
I'm assuming Order is unique for Module. If it isn't, JavaClassFileRecords may show up multiple times in the resultset.
If no module can be found for a JavaClassFile then it will not show up in the results. If you do want it to show up in cases like that (with a null module), replace INNER JOIN with LEFT OUTER JOIN.
SELECT j.ClassFile, m.Module
FROM JavaClassFileList j
INNER JOIN ModuleList m
ON m.Order =
(SELECT MAX(Order)
FROM ModuleList
WHERE Order < j.Order)
I have the following query which does a self join with a table and outputs all the points of intersections between lines.
insert into road_intersection
select nextval('road_intersection_id_seq'), a.road_id, b.road_id, st_intersection(a.road, b.road), st_centroid(st_intersection(a.road, b.road))
from polygon_road a, polygon_road b
where st_intersects(a.road, b.road) AND a.road_id!=b.road_id
BUT it outputs duplicate values for each point of intersection since it computes the point of intersection for each road. EG:
70;71;POINT_OF_INTERSECTION
71;70;POINT_OF_INTERSECTION
70 AND 71 are both id values of two distinct roads. As you can see the point of intersection has been computed twice for the same two roads.
Any suggestions how i can solve this issue and only one point of intersection would be computed?
Try something like:
select nextval('road_intersection_id_seq'),
a.road_id,
b.road_id,
st_intersection(a.road, b.road),
st_centroid(st_intersection(a.road, b.road))
from polygon_road a, polygon_road b
where st_intersects(a.road, b.road)
--AND a.road_id!=b.road_id --not needed any more
AND a.road_id < b.road_id
It will leave only one of the intersections (the one, where the first road has smaller id)