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27
votes
1answer
26k views

How do I get the current unix timestamp from PostgreSQL?

Unix timestamp is the number of seconds since midnight UTC January 1, 1970. How do I get the correct unix timestamp from PostgreSQL? When comparing to currenttimestamp.com and timestamp.1e5b.de I ...
7
votes
2answers
18k views

How to get the timestamp column in only milliseconds from PostgreSQL?

I have a column "created" with type timestamp without time zone default now() in a PostgreSQL database. If I select colums, it has a nice and readable format per default: SELECT created FROM ...
5
votes
2answers
12k views

MySQL Set UTC time as default timestamp

How do I set a timestamp column whose default value is the current UTC time? MySQL uses UTC_TIMESTAMP() function for UTC timestamp: mysql> SELECT UTC_TIMESTAMP(); +---------------------+ | ...
5
votes
2answers
1k views

Best way to handle dates prior to 1000 A.D. in MySQL?

I am creating a database for records that extend prior to 1000 AD, but MySQL Date and DateTime fields only support dates starting at 1000. Is there a way that would be more convenient than either ...
5
votes
2answers
1k views

Single data type for imprecise date values, as allowed by ISO 8601

How can I store date and time values with reduced precision in a PostgreSQL type, and have them behave as date and/or time values? ISO 8601 allows date values with reduced precision. ‘1964’, ...
5
votes
3answers
610 views

“AT TIME ZONE” with zone name PostgreSQL bug?

I was answering this stackoverflow question and found strange result: select * from pg_timezone_names where name = 'Europe/Berlin' ; name | abbrev | utc_offset | is_dst ...
5
votes
2answers
4k views

Storing time with milliseconds in database

Just a quick question regarding storing "time" in a database. I'm logging the time of users runs which are in the format 00:00:00:00 (hours, minutes, seconds, milliseconds). I was originally going to ...
4
votes
1answer
153 views

How can I improve this DB query? it takes too much time

The query is this: $today = $date->getTimestamp(); SELECT t.*, u.screen_name, u.profile_image_url FROM table AS t LEFT JOIN users AS u ON t.user_id=u.id_str WHERE ...
4
votes
2answers
60 views

List minutes instead of grouping by them

Looking how to list minutes 1 to 120 from a 2 hour interval timestamp field instead of getting each minute from both hours together. What I want is something like this: min COUNT(*) 1 ...
4
votes
2answers
662 views

Alternative to sequence and timestamp: uniquely ordering records in time

Oracle 11gR2 Exadata I'm required to uniquely identify when records are created in time. Sequence caching means I cannot use a sequence-based ID and batching inserts means that all records inserted ...
4
votes
2answers
5k views

How can I time-stamp data in MongoDB?

I'm responsible for writing an app to juggle a huge amount of client and business intelligence information. This information involves records for various businesses and metrics like revenue, their web ...
4
votes
2answers
126 views

Can a single SQL Server instance issue the same SYSDATETIME twice?

I am contemplating using a datetime2(7) as a clustered index. If I were to always populate that column using SYSDATETIME is it possible for the same instance to issue the same value twice (assuming ...
4
votes
1answer
163 views

MySQL year 2038 vulnerable

I was studying Drupal and asked this question: http://drupal.stackexchange.com/questions/45443/why-timestamp-format-was-chosen-for-users-created-field/45446#45446 I decided to check, how the CMS ...
3
votes
5answers
230 views

Using Timestamp plus Integer as Primary Key

In Sql Server, what would the drawbacks and disadvantages be of using a primary key that is: Two Character Table Identifier + YEAR + MONTH + DAY + HOUR + MINUTE + MILLISECOND + random integer between ...
3
votes
1answer
1k views

What happens when changing column type DATETIME to TIMESTAMP in MySQL?

I want to convert a column data type from DATETIME to TIMESTAMP in a table with more than one million of lines. Is it possible? Is it slow? Will I lose the old information or MySQL can convert this ...
3
votes
2answers
731 views

sql server management studio 2008 sucks up with memory yielding .net runtime failure

PROBLEM sql server management studio 2008 sucks up with memory yielding a .net runtime error. It crashes with an empty message in an error-dialog but there can be found a little eventlog entry, ...
3
votes
1answer
141 views

Why is add timestamp column with default not null so slow in Oracle 11g?

In Oracle I need to add a new column with type timestamp with time zone to a large table (80 million rows). I cannot have more than 30 - 60 seconds of downtime when I run it in production. This ...
3
votes
1answer
161 views

Timestamp on SSIS update on tsql

I have a couple of SSIS packages that copy the content of several tables to another db. One of the columns updated in the process is a timestamp datatype. From what I read this datatype can't be ...
3
votes
1answer
369 views

Retrieving queries when the hour of starting timestamp is less than the hour of ending timestamp

I have a CTE-based query in which I retrieve hourly intervals between two given timestamps. My query works as following: Getting start and end datetimes (let's say 07-13-2011 10:21:09 and 07-31-2011 ...
2
votes
2answers
9k views

Comparing date and timestamp variables in a where clause in a procedure

I have a variable in an Oracle stored procedure of DATE type (from user interface), and another of TIMESTAMP type (database is more precise than what the user would enter in the code that is executing ...
2
votes
3answers
2k views

Sorting by DATETIME slower than by TIMESTAMP?

I have the a DATETIME key on which I sort the results and the query is running quite slow. Will it run faster if I change it to TIMESTAMP ? Because I noticed that ordering by numbered keys is done ...
2
votes
1answer
5k views

Compare a date and a timestamp with time zone with now() in the same query?

I have multiple database servers I'm querying with a query that compares an expiration column with now(). The problem is that one of the servers' expiration column is a timestamp with time zone, and ...
2
votes
1answer
142 views

How to generate time in milliseconds in PostgreSQL stored procedure?

I have been reading the Postgres documentation about timestamps, but I am still a little bit confused. I need to store moments in times, measured in milliseconds, between the current time and ...
2
votes
1answer
297 views

datetime vs timestamp in mysql 5.5

What is the difference between datetime and timestamp in MySQL with respect to data being inserted from different timezones? Does anyone have any clues on this? I have a situation where I am trying ...
2
votes
1answer
396 views

MySQL unclearness about DataType TIMESTAMP with DefaultValue CURRENT_TIMESTAMP

In MySQL InnDB engine I created TableColumn with data type TIMESTAMP and put there as default value CURRENT_TIMESTAMP, but this value are always changed to CURRENT_TIMESTAMP when I update that by ...
2
votes
1answer
137 views

Implications of a second index on a timestamp field in a sequential table

I have a MySQL table of a few gigabytes with roughly ~100M rows. I store data sequentially, such that the timestamps increase as the ID also increases. Because ordering and filtering by the timestamp ...
2
votes
3answers
2k views

How do i subtract a number of days from a prepared statement parameter in db2?

I have a C# application using OLEDB to connect to a DB2 database. Basically, I want to do this: SELECT CALC.WEEK, COUNT(CALC.ID) AS TRANSACTIONS , SUM(CALC.SUBTOTAL) AS REVENUE FROM ( ...
2
votes
3answers
1k views

Finding five-minute interval prior to current time

I want to find the five minute interval just before the current time. So if the current time is 8:43 I want to return 8:35 and 8:40. Here is the query that I have written and it is working as ...
2
votes
0answers
453 views

Logic to convert a UTC date-time to a specific time zone

I have a table which has 1 row per event. Each event has a datetime stamp column which has values in UTC time. Each row has an associated local timezone in which the event occurred. I have a DIM ...
1
vote
1answer
270 views

How to convert a unix time to PostgreSQL' Timstamp without timezome?

I have a PostgreSQL database running on a server which has its time zone set to India's Time Zone (i.e. UTC +5:30) I have some data in a table which is created like this: CREATE TABLE "CLOUDDATA" ( ...
1
vote
2answers
132 views

Group Database Entries by time difference

I have a large postgreSQL database with log data. All this data has timestamps and I want to group consecutive rows where the difference between the timestamps is less then 1500 miliseconds for ...
1
vote
2answers
1k views

LEFT JOIN conversion to INNER JOIN, can't change FROM clause

I have 2 tables: BASE is master and is linked with CHILD via field ID: Left outer Join / 1:N relation. These 2 tables contain historised data, defined by 2 date-fields: start_date and end_date. ...
1
vote
2answers
2k views

How to set addtime(current_timestamp, '15:00:00') as MySQL timestamp column default value?

I want to set `addtime(current_timestamp, '15:00:00') as the default value of one MySQL table column. I tried to do this with the following command but failed: mysql> alter table mytable change c1 ...
1
vote
1answer
161 views

Difference between now() and current_timestamp

In PostgreSQL, I use the now() and current_timestamp function and I see no difference: # SELECT now(), current_timestamp; now | now ...
1
vote
2answers
485 views

INT or TIMESTAMP for the change time column in a logging table?

We're having an argument over what to use for storing change date in a new log table for our site. One side says, use INT for the timestamp, storing the UNIX timestamp. We can convert the datetime ...
1
vote
1answer
69 views

Deadline rule date input after now

Hi I'm trying to find a way to ensure deadlines inputted are later than the current time and date. Currently I'm attempting this with a rule. CREATE OR REPLACE RULE "DeadlineInput" AS ON INSERT ...
1
vote
1answer
316 views

TimeZone parameter in postgresql.conf

postgresql documentation says: All timezone-aware dates and times are stored internally in UTC. They are converted to local time in the zone specified by the timezone configuration parameter ...
1
vote
1answer
159 views

timestamp based concurrency

I am wondering if someone could help me out with a question I have about time stamp based concurrency. I found the following practice problem on a website It basically asks which of the following ...
1
vote
3answers
216 views

What happens when we take a timediff between timestamp and datetime

Say I have following table in mysql (5.5+): CREATE TABLE IF NOT EXISTS `test` ( `id` int(11) NOT NULL, `x_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, ...
1
vote
1answer
3k views

Why does mysql adds a default timestamp on insert/update even if I did not specify anything?

I have a table that is as follows: CREATE TABLE SomeTable ( id int unsigned NOT NULL AUTO_INCREMENT, status enum('broken','repaired') NOT NULL, from datetime NOT NULL, until ...
1
vote
1answer
573 views

MySQL cluster 5.6 doesn't convert invalid TIMESTAMP value to '0000-00-00 00:00:00'?

According to the document: Invalid DATE, DATETIME, or TIMESTAMP values are converted to the “zero” value of the appropriate type ('0000-00-00' or '0000-00-00 00:00:00'). but it doesn't ...
1
vote
1answer
49 views

Script to get duration

I am new to PostgreSQL. I am trying to write a query which can give me duration of the time. The fields are in the format yyyymmddhhmmss. In between we will get empty fields for Start_Time or ...
1
vote
1answer
4k views

How to compare (in MySQL) a DATETIME value to a TIMESTAMP value?

I'm trying to understand how to compare a DATETIME value (ostensibly inserted as GMT) and a TIMESTAMP value (automatically generated at INSERT time). As I understand it, the DATETIME is set to ...
1
vote
1answer
13 views

Select the last logged change before a specified time from a change list

I want to get the last change for all issues issue, that was made before a specified end time. I have 3 tables. projects +---+------------+ |ID |project_key | +---+------------+ |1 |bug_tracker | ...
1
vote
1answer
894 views

How to create trigger to update timestamp when record is updated or inserted in another table

I have a table t_task and a table t_taskaction with a foreign key to t_task. I would like to update timestamp from t_task that is refering the foreign key form t_taskaction with every update in ...
1
vote
1answer
811 views

MySQL 5.5.21 ON UPDATE CURRENT_TIMESTAMP incorrect

As the title says, I'm having a few issues with 'ON UPDATE CURRENT_TIMESTAMP'. Here is the SQL definition for the table: CREATE TABLE `judgements` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, ...
0
votes
4answers
9k views

Convert a Unix timestamp to a DATETIME in a View

I have a table that stores a unix timestamp. To query this as a date, I'm attempting to convert this timestamp to a datetime type in a view. Unfortunately, I can only seem to get the DATE portion out. ...
0
votes
1answer
521 views

Why are timestamps not always increasing with concurrent inserts?

I'm seeing some unexpected behavior with timestamp (rowversion) columns . I created a test table: create table Test ( Test_Key int identity(1,1) primary key clustered, Test_Value int, ...
0
votes
2answers
545 views

Dates changed to 0000-00-00

Previously, on my table (~81000 rows), I have had date and time fields set as VARCHAR instead of date/time. All those dates were of the type MM/DD/YY. I changed the type from VARCHAR to DATE and TIME ...
0
votes
1answer
191 views

How can I search a column in MySQL containing unix timestamps with a query referencing a different format?

I have a mysql table that contains something like: +-------------+-----------------+ | FOO1 | FOOTIME | +-------------+-----------------+ | blah | 1234567890000 | ...