indexing

问题 I am trying out Cloud Datastore's indexes, and I cannot figure out the configuration I need to resolve my queries. I have created a few entities of the same kind (named "object"), all of them with 5 properties named equally (property_0, property_1, ..., property_4). Then, I have created a composite index for that kind, indexing all 5 properties, and setting property_4 in the last place because I want to apply inequality filters on it. The definition of the index is: indexes: - kind: object

问题 In my dataframe, I get a '2' written over my index column's name. when I check for the columns name it doesn't show up there but as df.columns give this as output. I don't know how to remove that '2' from my dataset. I have tried removing index name but it hasn't solved my issue. df.columns ==> Output Index(['name', 'census 1981', 'census 1998', 'estimate 2000', 'calculation 2010', 'annual growth', 'latitude', 'longitude', 'parent division', 'name variants'], dtype='object', name=2) I expect

问题 In my dataframe, I get a '2' written over my index column's name. when I check for the columns name it doesn't show up there but as df.columns give this as output. I don't know how to remove that '2' from my dataset. I have tried removing index name but it hasn't solved my issue. df.columns ==> Output Index(['name', 'census 1981', 'census 1998', 'estimate 2000', 'calculation 2010', 'annual growth', 'latitude', 'longitude', 'parent division', 'name variants'], dtype='object', name=2) I expect

问题 This question already has an answer here : Select multiple ranges of columns in Pandas DataFrame (1 answer) Closed 2 years ago . What is the fastest way to drop columns[3] and columns[9:15] ? (I'm only able to remove the columns in 2 steps using the df.drop method) 1 2 3 4 5 6 .. n A x x x x x x .. x B x x x x x x .. x C x x x x x x .. x 回答1: You can, in fact, use pd.DataFrame.drop in one step. You can use np.r_ to combine multiple indices and ranges. Here's a demo: df = pd.DataFrame(np

问题 The documentation states: However, if you have a filter with a range comparison (<, <=, >, >=), your first ordering must be on the same field: That implies that I can use the non-range comparison, "==", with the orderBy clause. But this fails: myCollectionRef.where('age', '==', 2).orderBy('name'); 回答1: If you wanted to order a query with one or more equality filters, where the ordering is by a different field, you'll need to create a composite index. You can read more about this in our

问题 The documentation states: However, if you have a filter with a range comparison (<, <=, >, >=), your first ordering must be on the same field: That implies that I can use the non-range comparison, "==", with the orderBy clause. But this fails: myCollectionRef.where('age', '==', 2).orderBy('name'); 回答1: If you wanted to order a query with one or more equality filters, where the ordering is by a different field, you'll need to create a composite index. You can read more about this in our

问题 I have something in bash like myArray=('red' 'orange' 'green') And I would like to do something like echo ${myArray['green']} Which in this case would output 2 . Is this achievable? 回答1: This will do it: #!/bin/bash my_array=(red orange green) value='green' for i in "${!my_array[@]}"; do if [[ "${my_array[$i]}" = "${value}" ]]; then echo "${i}"; fi done Obviously, if you turn this into a function (e.g. get_index() ) - you can make it generic 回答2: You must declare your array before use with

问题 I have created a cluster create cluster abc_clus (abc_key int) ; and then created an index based on that cluster create index abc_clus_idx on cluster abc_clus; I tried adding this cluster on these 4 tables for a complex join create table number1 ( dateofbirth date, Time timestamp(0), IDnumber int not null, class varchar(7) not null, primary key (dateofbirth, Time, class)) cluster abc_clus(class); and create table number2( tutornumber int not null, forename varchar2(20) not null, constraint

问题 I am a beginner at Python, and to those who holds negative thoughts against my post, please leave. I am simply seeking help here and trying to learn. I'm trying to check within a simple data set the 0s and 1s. This will be used towards defining voids and solids on floor plans to define zones in buildings... eventually 0s and 1s will be swapped out with coordinates. I am getting this error: ValueError: [0, 3] is not in list I am simply checking if one list is contained in the other.

问题 I have what I thought was a simple query on a collection called 'email': const emailQuery = admin .firestore() .collection('email') .where('sendAt', '>=', new Date()) .where('orderId', '==', doc.orderId) .where('brandId', '==', doc.brandId); I'm receiving the error in the subject of this post, indicating that I need to create an index for this query. I've tried creating a couple for the relevant fields, but I'm unsure of why it's needed since only one field is ordered--and the error remains