Specifies the type of data being stored (string, date, numeric, etc).

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1answer
3k views

How do I decompose ctid into page and row numbers?

Each row in a table has a system column ctid of type tid that represents the physical location of the row: begin; create table t(id serial); insert into t default values; insert into t default ...
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votes
2answers
3k views

What is the best identifier for a UserID? 64 bit integers, UUID V5, or 64 character SHA256 UID?

I wish to future-proof my application. What is the best type of identifier to use? I am considering: 64 bit Integer UUID 64 character SHA256 I am not developing a distributed system, so is ...
5
votes
1answer
11k views

Why aren't unsigned integer types available in the top database platforms?

Databases are usually very customizable with varying data types and custom lengths. It surprises me, as I try to look for the syntax to use unsigned int types that they are not available from neither ...
5
votes
2answers
3k views

Why do I get leading zeros when converting from decimal to char in a db2 query?

I have a column named length defined as: TYPE_NAME: DECIMAL DATA_TYPE: 3 COLUMN_SIZE: 9 BUFFER_LENGTH: 11 DECIMAL_DIGITS: 5 NUM_PREC_RADIX: 10 When I run the following select: select ...
5
votes
2answers
550 views

Determining the optimal Column Widths from a .csv File

I want to import a .CSV file into a MySQL Table. I would like to determine the optimal column widths to use based on the actual data contained in the CSV file. Are there any scripts or utilities to ...
5
votes
0answers
188 views

Which SQL datatypes exist since when and in which RDBMS? [closed]

I found a general comparision of different SQL implementations that only covers some data types (BOOLEAN and TIMESTAMP) and a comparision of datat type support in different RDBMS from 2009 that does ...
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votes
2answers
12k views

A Script to insert dummy Data in all tables of Database

I wanted a Script that can loop through all tables and their columns in the database and insert dummy data based on column type and size, so that i can start using the database for testing, and ...
4
votes
3answers
12k views

How to change the datatype of a column from integer to money?

I am attempting to convert a PostgreSQL table column from integer to money, but I am receiving the error: cannot cast type MyColumn to money I have tried these two statements, but just haven't ...
4
votes
3answers
491 views

Unknown returned type in PostgreSQL query

The following query works: SELECT a, b FROM unnest(ARRAY[(1,2), (3,4)]) AS t(a integer, b integer); a b _ _ 1 2 3 2 However, I wasn't able to use a different column type such as varchar(255): ...
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1answer
5k views

Datatype bigger than bigint

I want to use dataype which can hold more than 19 digits. So is there any datatype available which can hold larger than 19 digits?
4
votes
1answer
4k views

query to identify all data types used in postgresql database tables

I don't want to know all data types, just all data types used in my database. Can this information be queried? PostgreSQL 8.4 and 9.x versions I currently need to know all data types for over 200 ...
4
votes
3answers
137 views

Get Stored Procedure Result Column Types

I'm trying to get whatever a stored procedure returns, with the column names and their types. I can do this with tables but I couldn't figure it out for stored procedures. I tried the sp_columns but ...
4
votes
1answer
2k views

Do SQL Server Views update their data types automatically based on what tables feed them?

Someone mistakenly created a bunch of nchar fields in database tables. I noticed this, and after examining the issue, we're moving these fields to nvarchar types and trimming the values inside. In my ...
4
votes
1answer
16k views

Changing a column data type from datetime to float

I have a table with a float column. All values in this column for all records are NULL. I want to change the data type to datetime. I executed the query: ALTER TABLE MyTable ALTER Column MyColumn ...
4
votes
1answer
217 views

Why does postgres use more space for a time with timezone than a timestamp with timezone?

The documentation on date/time data types state that timestamp with timezone takes 8 bytes, while time with timezone takes 12 bytes. They both have the same resolution (1 microsecond), and on the face ...
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votes
2answers
1k views

Change column data type across database

I have a bunch of tables with many columns of data type ntext. I wish to change all such columns in all tables of a particular database to nvarchar(max), because of planned deprecation (EDIT: also ...
4
votes
2answers
924 views

How can I enforce ensure uniqueness of an association with a time dimension?

I have a database table AB which tracks the association of A and B over time: create table AB columns ( ARef ..., -- FK of A BRef ..., -- FK of B Since as Timestamp, Until as Timestamp, ...
4
votes
1answer
880 views

Why does using a Real data type in a mathematical equation return an incorrect result?

I was trying to figure out the source of what appeared to be a rounding error today, and discovered that one of the columns used in a mathematical equation was using the real data type, and this is ...
4
votes
1answer
1k views

Does creating an index on BIT(n) attribute in MySQL make sense?

I am working on a very specific thing and I need to use BIT(n) attributes and efficiently search through them. n is generally not a power of 2. I've seen some mentions on the internet that BIT ...
4
votes
1answer
162 views

Data type for a fuzzy date?

I want to store partial information related to a date. I might know the year and month but not the day. I might know the day and month but not the year. I might know the date lies in an open or closed ...
4
votes
1answer
370 views

Storing phone number in E.164

TLDR; If I store a phone number in MySQL(or any DB with equivalent constraints), would the correct format be E.164 values into a VARCHAR(32) field? Have been reading up on format/storage of ...
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votes
3answers
3k views

MySQL datatype for username of maximum 15 characters

I currently have a database with the "user" table having username as one of the columns. I allow a maximum of 15 characters for the username in my system. Is it fine to have the username column as a ...
4
votes
1answer
238 views

How to set constraints on UDT in SQL Server 2005 - 2012

I'm creating my UDT: CREATE TYPE [dbo].[Code] FROM VARCHAR(20) NOT NULL As RULES and DEFAULTS are considered deprecated, what is the recommended way to set constraint on my type to make sure that ...
3
votes
1answer
1k views

Why 't' and 'f' instead of TRUE and FALSE

Why does PostgreSQL return 't' and 'f' instead of TRUE and FALSE? The documentation itself advises us to use TRUE and FALSE when inserting boolean values or making comparisons, but returns a ...
3
votes
3answers
163 views

How to restrict sequence like ID type to C type like int64_t, uint64_t, int32_t?

In C99 I can be pretty clear about the size/domain of an integer type. When interfacing a SQL database like Oracle or Postgresql from a C program I want to create a table with integer types that ...
3
votes
2answers
7k views

what is bigger than a longblob?

the longblob is the biggest data type of Mysql. If I want to save something bigger than 4gb (longblob) how can I do?. I'm talking about Mysql v-5.+
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votes
2answers
1k views

Mapping SQL Server integer to Oracle Datatype

Well I know, that an SQL Server integer is best represented by NUMBER(10). But sometimes I have migrate some maintenance scripts to Oracle and I wonder if I must carefully map integer to NUMBER(10) ...
3
votes
1answer
1k views

PostgreSQL SELECT primary key as “serial” or “bigserial”

I've meshed together a way to determine what the data_type is as in the data_type you use in the syntax when creating a new table based off of the PostgreSQL wiki page. If there is something wrong ...
3
votes
2answers
293 views

How to save an interval of years in postgresql

I have to save an interval of years, like: id intervalYears 1 2014/2015 2 2015/2016 3 2016/2017 And so on. Those years are like accademic years, so the first year must be lesser then the second, ...
3
votes
1answer
2k views

Oracle integer to number conversion

According to the Oracle documentation, creating a table with a column of ANSI type INT, Oracle will convert it to NUMBER(38). According to the same document, NUMBER(38) is supposed to be a NUMBER ...
3
votes
2answers
242 views

Are mime types only for file storage? [closed]

If I have a plain-text field on a web form (not a file upload) inserting its content into my table, would it be wrong for me to set a mime type 'text' to it, or would it be safer?
3
votes
1answer
96 views

Do fixed-width rows improve PostgreSQL read performance?

I have a table articles: Table "articles" Column | Type | Modifiers | ...
3
votes
1answer
147 views

Slow window function query with big table

I'm doing some performance testing on a new DB design on PostgreSQL 9.4rc1 and I'm seeing some pretty slow queries using window functions. Here is my table setup: CREATE TABLE player_stat ( ...
3
votes
2answers
270 views

Moving data from table with VARCHAR(50) fields to table with numeric fields increases table size

I want to understand why migrating data in a table with all VARCHAR(50) fields to a table with optimized smaller types caused the new table (containing 61,065,164 rows) to be 4.46 GB, which is larger ...
3
votes
3answers
4k views

What data type should I use: ENUM, TINYINT, or CHAR?

I'm creating a new table and I would like to do it right. The table will be a list of members with their Professional Type and Decile associated. The Professional Type is a 3-character string. There ...
3
votes
3answers
2k views

Estimate large database size and speed

First I want to know how to estimate the database size regarding the biggest table it will contains. I've the following : +----------+------------------+------+-----+---------+-------+ | Field | ...
3
votes
1answer
52 views

Find current owner of custom data type?

In Postgresql, when I try to run ALTER TYPE x ADD VALUE y; on a custom datatype I get an error stating PG::Error: ERROR: must be owner of type x. I know this can be solved by running ALTER TYPE x ...
3
votes
1answer
936 views

Cannot SUM datetime field in SQL Server migrated from Access

I am new here and am new to SQL Server (Express). I used the SSMA tool and it converted Access date/time fields to datatime2. The data contains duration data so there is no need for a date. I want to ...
3
votes
2answers
8k views

changing float->numeric casts from assignment to implicit, dangerous?

In porting an application to PostgreSQL (9.1), one odd SQL incompatibility I've discovered concerns the round() function, specifically the version that takes a second argument indicating the rounding ...
3
votes
1answer
2k views

Oracle implicit parameter casting - why doesn't it always work? (ORA-06502 error)

I have a Java (Spring) app that uses Oracle 10 as DB. Some legacy code has wrong parametrization of PL/SQL procedures. For instance, some input parameters are declared as OracleTypes.VARCHAR in Java ...
3
votes
1answer
41 views

Handling sql column with mixed varchar and float data types

We have some Excel spreadsheets with parcel numbers for properties that should be in a standard varchar format similar to: [Parcel # 1] [Building Address] 038-60-171-16-000 1750 W 4th St ...
3
votes
1answer
368 views

Use of integer instead of interval (of one type)

Our DB design presently has a interval column which will only be storing days (no other interval type) so it is making sense to use INT2 (smallint) instead of interval. Reference to documentation. ...
3
votes
1answer
81 views

date type implicit conversion

When does oracle implicitly converts date type? on what parameters does it depend? I am running the following: SELECT SYSDATE - '01-01-01' FROM DUAL and got : SELECT SYSDATE - '01-01-01' FROM ...
3
votes
1answer
984 views

SELECT in trigger function in two tables

My table and trigger in PostgreSQL 9.4.3 on x86_64-unknown-linux-gnu, compiled by gcc (Debian 4.9.2-10) 4.9.2, 64-bit: CREATE TABLE measurements ( measurement_id SERIAL PRIMARY KEY NOT NULL, ...
3
votes
1answer
43 views

Why does the behavior of array syntax differ from '(?,?)' syntax when updating a point field and that field is NULL?

I'm using PostgreSQL 9.3.5. Suppose I have the following table: CREATE TEMPORARY TABLE point_test ("name" varchar(255), "pt" point); I then insert a row, leaving pt NULL: INSERT INTO point_test ...
3
votes
1answer
449 views

Good layout of 3d point data for spatial queries in Postgres?

Like shown in another question, I deal with a lot (>10,000,000) entries of points in a 3D space. These points are defined like this: CREATE TYPE float3d AS ( x real, y real, z real); If I am ...
3
votes
2answers
49 views

What data type are the numbers in a SQL Server statistics object?

Specifically I'm most interested in: The 'All density' number in the density vector Numbers in the histogram E.g. are they floats / decimals? What precision / scale / length do they have? The ...
3
votes
1answer
1k views

Rich text: VARCHAR, TEXT or BLOB in MySQL

Question: In my web application (php/MySQL) I will be saving rich text. This may be anything from a couple words to several pages length essay. I’m sure I could get away with using VARCHAR, TEXT or ...
3
votes
1answer
46 views

Is 'internallength' always useful in custom type definition in Postgres?

In our database we use a custom type to store 3D locations: CREATE TYPE float3d AS ( x real, y real, z real); In many examples I see INTERNALLENGTH used as a parameter with the definition of ...
3
votes
2answers
61 views

MySQL is trimming my numbers and I can't figure out why

I've got a table with a bunch of decimal(12,2) fields that are supposed to hold money amounts. For some reason which I can't figure out one of them is trimming the value when either inserted or ...