allocate. If set to '-1', no limit is imposed. If set to '0', no change of the memory limit is attempted and the php.ini memory_limit is used. This setting is used while importing/exporting dump files so affect smaller dumps and allows users to create larger dumps that won’t otherwise fit in memory due to php memory limit. Produced files contain more GZip/BZip2 headers, but all normal programs handle this this directory and how to make its usage secure. See also See 1.16 I cannot upload big dump files (memory, HTTP or timeout problems). for alternatives. Type: Default value: Type: Default value: $cfg['SaveDir']

allocate. If set to '-1', no limit is imposed. If set to '0', no change of the memory limit is attempted and the php.ini memory_limit is used. This setting is used while importing/exporting dump files so affect smaller dumps and allows users to create larger dumps that won’t otherwise fit in memory due to php memory limit. Produced files contain more GZip/BZip2 headers, but all normal programs handle this directory and how to make its usage secure. See also: See 1.16 I cannot upload big dump files (memory, HTTP or timeout problems). for alternatives. $cfg['SaveDir'] Type string Default value '' The

the name, which suggests a kind of “nothing” that won’t do any harm if you add it to a number or stick it to the back of a string. In reality, performing such operations will render the entire expression expressions that contain NULL or may resolve to NULL. If you only need a quick reference to refresh your memory, go to the summary at the end of the guide. So — what is it? In SQL, NULL is not a value. It is to more confusion than NULL, and yet its workings shouldn’t be hard to understand as long as you stick to the following simple definition: NULL means unknown. Let me repeat that: NULL means UNKNOWN

Systems 260 Validating Your Systems 0 Validating Network Performance 260 Validating Disk I/O and Memory Bandwidth 261 To run the disk and stream tests 261 Initializing a Greenplum Database System 262 Storage 308 Security 308 Amazon Web Services (AWS) 308 Virtual Machine Type 308 Compute 309 Memory 309 Network 309 Storage 309 Elastic Block Storage (EBS) 309 Ephemeral 310 AWS Recommendations Master 310 Segments 310 Google Compute Platform (GCP) 310 Virtual Machine Type 310 Compute 310 Memory 310 Network 311 VMware Greenplum v6.18 Documentation VMware, Inc. 13 Storage 311 GCP Recommendations

Systems 268 Validating Your Systems 0 Validating Network Performance 268 Validating Disk I/O and Memory Bandwidth 269 To run the disk and stream tests 269 Initializing a Greenplum Database System 270 Storage 317 Security 317 Amazon Web Services (AWS) 317 Virtual Machine Type 317 Compute 318 Memory 318 Network 318 Storage 318 Elastic Block Storage (EBS) 318 Ephemeral 319 AWS Recommendations Master 319 Segments 319 Google Compute Platform (GCP) 319 Virtual Machine Type 319 Compute 319 Memory 319 Network 320 Storage 320 GCP Recommendations 320 Master and Segment Instances 320 Azure 321

Systems 193 Validating Your Systems 0 Validating Network Performance 194 Validating Disk I/O and Memory Bandwidth 195 To run the disk and stream tests 195 Initializing a Greenplum Database System 195 241 Virtual Machine Type 241 Compute 242 VMware Greenplum v6.17 Documentation VMware, Inc. 9 Memory 242 Network 242 Storage 242 Elastic Block Storage (EBS) 242 Ephemeral 243 AWS Recommendations Type 243 Compute 243 Memory 243 Network 244 Storage 244 GCP Recommendations 244 Master and Segment Instances 244 Azure 245 Virtual Machine Type 245 Compute 245 Memory 245 Network 245 Storage

Steps 265 Validating Your Systems 265 Validating Network Performance 266 Validating Disk I/O and Memory Bandwidth 266 To run the disk and stream tests 267 Initializing a Greenplum Database System 267 Storage 312 Security 312 Amazon Web Services (AWS) 312 Virtual Machine Type 312 Compute 313 Memory 313 Network 313 Storage 313 Elastic Block Storage (EBS) 313 Ephemeral 314 AWS Recommendations Type 314 Compute 314 Memory 314 Network 315 Storage 315 GCP Recommendations 315 Master and Segment Instances 315 Azure 316 Virtual Machine Type 316 Compute 316 Memory 316 Network 316 Storage

Support Functions ..................................................................... 1478 47.3. Memory Management ............................................................................. 1487 47 pg_available_extension_versions ............................................ 2335 52.67. pg_backend_memory_contexts ..................................................... 2336 52.68. pg_config ........... pg_available_extension_versions Columns ............................................... 2335 52.68. pg_backend_memory_contexts Columns ........................................................ 2336 52.69. pg_config Columns

Interface Support Functions ................................................................ 1401 47.3. Memory Management ....................................................................... 1410 47.4. Transaction 66. pg_available_extension_versions ...................................... 2208 52.67. pg_backend_memory_contexts ................................................ 2209 52.68. pg_config ................ pg_available_extension_versions Columns ......................................... 2209 52.68. pg_backend_memory_contexts Columns ................................................... 2209 52.69. pg_config Columns

Support Functions ..................................................................... 1430 46.3. Memory Management ............................................................................. 1439 46 contract. • Platform information. This includes the kernel name and version, C library, processor, memory infor- mation, and so on. In most cases it is sufficient to report the vendor and version, but do example. The date type is actually quite flexible in what it accepts, but for this tutorial we will stick to the unambiguous format shown here. 9 The SQL Language The point type requires a coordinate pair